Illyrian warfare


The history of Illyrian warfare of the Illyrians spans from the beginning of the 2nd millennium BC up to the 1st century AD in the region of Illyria and in southern Italy where the Iapygian civilization flourished.
It concerns the armed conflicts of the Illyrian tribes and their kingdoms in the Balkans in Italy as well as pirate activity in Mediterranean. Apart from conflicts between Illyrians and neighbouring nations and tribes, numerous wars were recorded among Illyrian tribes themselves.
Illyrians were renowned warriors, according to ancient sources. They were known as skilled craftsmen and shipbuilders in ancient times and controlled much of the Adriatic and Ionian Sea using their numerous warships. Illyrians had effective weapons such as the sica, a curved-tip sword that originated in Illyria and was eventually adopted all over the Balkans and used later by the Romans.

Mythological

Instances of Illyrians engaged in armed conflict occurred in Greek mythology and specifically in the legend of Cadmus and Harmonia, where Cadmus led the Illyrian Enchelii in a victorious campaign against the Illyrians after a divine advice from the Oracle. If the legend is true this war would have occurred around 2000 BC, the time when Cadmus has been claimed to have lived.

Tribal conflicts

Illyrian tribes were reluctant to help each other in times of war and even fought amongst each other and they sometimes allied with the neighbouring Romans and Greeks: These conflicts happened because of land, pastures and areas of natural substances such as iron and salt. The Romans, before they conquered Illyria, were involved in tribal conflicts and used them to their advantage. The most known incident is the involvement of the Romans in a war between the Dalmatians and the Liburnians over Promona, which in the end were encouraged to take peace. Commonly the Romans were ordered to act as referees in their bloody fights. The tribe of Autariatae fought against the Ardiaei for control of valuable salt mines. The Ardiaei were notorious before being defeated by the Romans. The Daorsi had suffered attacks from the Delmatae to the extent that they requested Roman aid.

States

The earliest recorded Illyrian Kingdom was that of the Enchele in the 8th century BC. The Enchele held dominance for two centuries until their state crumbled from the start of the 6th century BC. After the Enchelii the Taulanti formed their own state in the 7th century BC. The Autariatae under Pleurias were a kingdom. The Kingdom of the Ardiaei began at 230 BC and ended at 167 BC. The most notable Illyrian kingdoms and dynasties were those of Bardyllis of the Dardani and of Agron of the Ardiaei who created the last and best-known Illyrian kingdom. Agron ruled over the Ardiaei and had extended his rule to other tribes as well. As for the Dardanians, they always had separate domains from the rest of the Illyrians.
The Illyrian kingdoms were composed of small areas within region of Illyria. The exact extent of even the most prominent ones remains unknown. Only the Romans ruled the entire region. The internal organization of the south Illyrian kingdoms points to imitation of their neigh boring Greek kingdoms and influence from the Greek and Hellenistic world in the growth of their urban centres. Polybius gives us an image of society within an Illyrian kingdom as peasant infantry fought under aristocrats which he calls in Greek Polydynastae where each one controlled a town within the kingdom. The monarchy was established on hereditary lines and Illyrian rulers used marriages as a means of alliance with other powers. Pliny writes that the people that formed the nucleus of the Illyrian kingdom were 'Illyrians proper' or Illyrii Proprie Dicti. They were the Taulantii, the Pleraei, the Endirudini, Sasaei, Grabaei and the Labeatae. These later joined to form the Docleatae.

Liburnian thalassocracy

Navigable skills and mobility of the Liburnians on their swift ships, the Liburna allowed them to be present, very early, not only along the Eastern Adriatic coast, they reached also the opposite, western, Italic coast. This process started during great Pannonian-Adriatic movements and migrations at the end of the Bronze Age, from the 12th to 10th century BC. In the Iron Age, they were already in the Italic coast, establishing colonies in Apulia and especially in Picenum, where specific Iron Age cultures developed.
From the 9th to the 6th century BC there was certain koine – cultural unity in the Adriatic, with the general Liburninan seal, whose naval supremacy meant both political and economical authority through several centuries. Some similar toponyms attested not only Liburnian but also other Illyrian migrations to the central and south Italy, respectively Apulia and Picenum.
In the 9th century BC their ruled the inner Adriatic sea and in the first half of the 8th century BC they expanded southwards. According to Strabo, the Liburnians became masters of island of Corcyra, making it their most southern outpost, by which they controlled the passage into the Adriatic Sea. In 735 BC, they abandoned it, under pressure of Corinthian ruler Hersikrates, during the period of Corinthian expansion to South Italy, Sicily and the Ionian Sea. However, their position in the Adriatic Sea was still strong in the next few centuries. Corinth was the first that went up against the Liburnians. The Bacchiade expelled the Liburni and the Eretrians from Corcyra. About 625 BC, the Taulantii asked for the aid of Corinth and Corcyra against the Liburni. The Greeks were victorious.
Liburnian control of the Adriatic Sea coasts started to decrease in the 6th century BC. According to Pliny the Elder, the Liburnians lost supremacy in the Western Adriatic coast due to invasion of the Umbri and the Gauls, obviously caused by strengthening and expansion of the Etruscan union in the 6th century BC, whose rich material presence in the basin of Po river, undoubtedly meant weakening of the Liburnian thalassocracy influence in the north-west of Adriatic. Celtic breaks to the Italian peninsula, after 400 BC, significantly changed ethnic and political picture there, it directly imperilled remaining Liburnian possessions on the western coast.
Unlike at the western Adriatic coast, Celtic raids to the narrow Liburnian region at the eastern Adriatic coast were peripheral in geographical meaning. Despite of recorded material exchange, Celtic archaeological forms are marginal and secondary in regions settled by Histri, Iapodes, Dalmatae and are especially rare in Liburnian Iron Age heritage.

Iapygian–Tarentine Wars

The Iapygian-Tarentine Wars were a set of conflicts and wars between the Greek colony of Taras and the three Iapygian peoples, Messapians, Peucetii and Daunians.
Conflicts started immediately after the foundation of Tars in 706 BC over domination of the fertile adjacent plains in southern Italy. The expansion of Taranto was limited to the coast because of the resistance of the populations of inner Apulia. In 473 BC, Taranto signed an alliance with Rhegion, to counter the Messapii, Peuceti, and Lucanians, but the joint armies of the Tarentines and Rhegines were defeated near Kailìa, in what Herodotus claims to be the greatest slaughter of Greeks in his knowledge, with 3,000 Reggians and uncountable Tarentines killed. In 466 BC, Taranto was again defeated by the Iapyges; according to Aristotle, who praises its government, there were so many aristocrats killed that the democratic party was able to get the power, to remove the monarchy, inaugurate a democracy, and expel the Pythagoreans.
In c.440 BC the Messapian city-state of Brindisi entered into an alliance with Thurii. The Brindisi-Thurri army had a leadership advantage in the form of Cleandridas, an exiled Spartan general who had been banished from the Peloponnese for accepting an Athenian bribe as an advisor of the Spartan king Pleistoanax. Taranto supported the Peloponnesian side against Athens in the Peloponnesian War, refused anchorage and water to Athens in 415 BC, and even sent ships to help the Peloponnesians, after the Athenian disaster in Sicily. On the other side, Athens supported the Messapians, in order to counter Taranto power.
After 330 BC the Messapians joined forces with the Tarentines against an even greater force, that of Rome. The alliances with Taras and with Cleonimus of Sparta in 304 BC was an anti-Roman campaign. Thus towards the end of the fourth century Rome had become a common enemy for both the Iapygians and the Tarentines, even as far as ending the prolonged battles and causing them to make an alliance.

Illyrian expansion

In the 4th century BC Bardyllis became king of the Illyrians and creator of a new dynasty after overthrowing Sirras, the previous Illyrian king, who had entered in a peace treaty over the control of Lyncestis. Bardyllis succeeded in bringing various tribes into a single organisation and soon became a formidable power in the Balkans, resulting in a change of relations with Macedonia. Using new war tactics in 393 BC the Illyrians won a decisive battle against Amyntas III, expelling him and ruling Macedonia through a puppet king. in 392 BC Amyntas III allied himself with the Thessalians and took Macedonia under his rule, taking it from the Dardanians. After continuous invasions Bardyllis forced the Macedonians to pay him an annual tribute in 372 BC.
In 385 BC Bardyllis raided Epirus which was under Molossian rule. This time the Illyrians were allied with and aided by Dionysius of Syracuse to place Alcetas, who was a refugee in his court, to the throne. Dionysius planned to control all the Ionian Sea. Sparta had intervened as soon as the events became known and expelled the Illyrians who were led by Bardyllis. Despite being aided by 2000 Greek hoplites and five hundred suits of Greek armour, the Illyrians were defeated by the Spartans led by Agesilaus but not before ravaging the region and killing 15,000 Molossians. Thus their attempt to control Epirus failed. In 360 BC, another Illyrian attack forced the Molossian king Arymbas to evacuate his non-combatant population to Aetolia and let the Illyrians loot freely. The worked and the Molossians fell upon the Illyrians who were encumbered with booty and defeated them. In the same year Arymbas of the Mollosians defeated the Illyrians after they raided and looted Epirus.
In 360 BC the southern Paeonian tribes launched raids against Macedonia in support of an Illyrian invasion. In 359 BC Bardyllis won a decisive battle against the Macedonian king Perdiccas III in which the king himself was killed along with 4,000 of his soldiers and the Illyrians occupied the cities of upper Macedonia. The Macedonian king's attempt to reconquer upper Macedonia had failed.
Following the disastrous defeat of the Macedonians by Bardyllis, when king Philip took control of Macedonian throne in 358 BC, he reaffirmed the treaty with the Illyrians, marrying the Illyrian princess Audata, probably the daughter or the niece of Bardyllis. This gave Philip valuable time to gather his forces and to defeat the Illyrians, who were still under Bardyllis, in the decisive Erigon Valley battle by killing about 7,000 and eliminating the Illyrian menace for some time. In this battle Bardyllis himself was killed at the age of 90 after Philip II refused a peace treaty offered by the Illyrians. In 335 BC the southern Illyrian states were all subjected by Alexander the Great and only at the end of the 4th century BC won their independence.
In 358 BC Phillip of Macedon defeated Bardyllis, Diodorus Siculus writes this of the event;

And at first for a long while the battle was evenly poised because of the exceeding gallantry displayed on both sides, and as many were slain and still more wounded, the fortune of battle vacillated first one way then the other, being constantly swayed by the valorous deeds of the combatants; but later as the horsemen pressed on from the flank and rear and Philip with the flower of his troops fought with true heroism, the mass of the Illyrians was compelled to take hastily to flight. When the pursuit had been kept up for a considerable distance and many had been slain in their flight, Philip recalled the Macedonians with the trumpet and erecting a trophy of victory buried his own dead, while the Illyrians, having sent ambassadors and withdrawn from all the Macedonian cities, obtained peace. But more than seven thousand Illyrians were slain in this battle.

Gallic invasions

From the 4th century BC, Celtic groups pushed into the Carpathian region and the Danube basin, coinciding with their movement into Italy. According to legend, 300,000 Celts moved into Italy and Illyria. By the 3rd century, the native inhabitants of Pannonia were almost completely Celticized. The Illyrians had been waging war against the Greeks, leaving their western flank weak. Whilst Alexander ruled Greece, the Celts dared not to push south near Greece. Therefore, early Celtic expeditions were concentrated against Illyrian tribes.
We have little information about the affairs in the Illyrian hinterland, but we do know that the first Balkan tribe to be defeated by the Celts was the Autariatae, who during the 4th century had enjoyed a hegemony over much of the central Balkans, centred on the Morava valley. An interesting account of cunning Celtic tactics is revealed in their attacks on the Ardiaei. In 310 BC, Celtic general Molistomos attacked deep into Illyrian territory, subduing the Dardanians and the Paeonians.
In 280 BC they moved in three directions: toward Macedonia and Illyria, toward Greece, and toward Thrace. The main army according to Diodorus, of 150,000-foot soldiers equipped with great shields and 10,000 horsemen was followed by 2,000 wagons transporting food and equipment. All the states of the Balkans at this time looked at this movement with apprehension. Ptolemy, the king of Macedonia, took the news of the Gauls casually. He looked down with derision on the proposal of the king of the Dardanians possibly Monunius who sent delegates to say that they could offer 20,000 warriors to assist him. In an insulting manner, he said that the work was for the Macedonians to do. When the king of the Dardanians was told of this, he replied that the soon glorious Macedonian kingdom would fall because of the immaturity of a youth. And so it happened, for in the battle that took place a few days later in Macedonia, the Macedonian army was routed and Ptolemy was wounded and taken prisoner. After continuing south and raiding the Delphi the Gallic army decided to return up north to their homeland but were all wiped out by the Dardanians, through which they had to pass.

Illyrian wars

In the First Illyrian War, which lasted from 229 BC to 228 BC, Rome's concern with the trade routes running across the Adriatic Sea increased after the First Punic War, when many tribes of Illyria became united under one queen, Teuta. The death of a Roman envoy named Coruncanius on the orders of Teuta and the attack on trading vessels owned by Italian merchants under Rome's protection, prompted the Roman senate to dispatch a Roman army under the command of the consuls Lucius Postumius Albinus and Gnaeus Fulvius Centumalus. Rome expelled Illyrian garrisons at the Greek cities Epidamnus, Apollonia, Korkyra, Pharos and others and established a protectorate over these Greek towns.
The Romans also set up Demetrius of Pharos as a power in Illyria to counterbalance the power of Teuta.
The Second Illyrian War lasted from 220 BC to 219 BC. In 219 BC the Roman Republic was at war with the Celts of Cisalpine Gaul, and the Second Punic War with Carthage was beginning. These distractions gave Demetrius the time he needed to build a new Illyrian war fleet. Leading this fleet of 90 ships, Demetrius sailed south of Lissus, violating his earlier treaty and starting the war.
Demetrius' fleet first attacked Pylos where he captured 50 ships after several attempts. From Pylos the fleet sailed to the Cyclades, quelling resistance they found on the way. Demetrius foolishly sent a fleet across the Adriatic, and, with the Illyrian forces divided, the fortified city of Dimale was captured by the Roman fleet under Lucius Aemilius Paulus. From Dimale the navy went towards Pharos. The forces of Rome routed the Illyrians and Demetrius fled to Macedon where he became a trusted councillor at the court of Philip V of Macedon, and remained until his death at Messene in 214 BC.
During the Third Illyrian War in 168 BC the Illyrian king Gentius allied himself with the Macedonians. First in 171 BC, he was allied with the Romans against the Macedonians, but in 169 he changed sides and allied himself with Perseus of Macedon. He arrested two Roman legati and destroyed the cities of Apollonia and Dyrrhachium, which were allied with Rome. In 168 he was defeated at Scodra by a Roman force under L. Anicius Gallus, and in 167 brought to Rome as a captive to participate in Gallus' triumph, after which he was interned in Iguvium. In the Illyrian War of 229 BC, 219 BC and 168 BC, Rome overran the Illyrian settlements and suppressed piracy, which had made Adriatic Sea an unsafe region for Roman commerce. There were three Roman campaigns: the first against Teuta the second against Demetrius of Pharos and the third against Gentius. The first Roman campaign of 229 BC marked the first time that the Roman Navy crossed the Adriatic in order to launch the invasion.

Great Illyrian revolt

The Great Illyrian Revolt, was a major conflict between an alliance of Illyrian communities and the Roman forces that lasted for four years beginning in AD 6 and ending in AD 9. In AD 6, several regiments of Daesitiates, natives of area that now comprises central Bosnia and Herzegovina, led by Bato the Daesitiate, were gathered in one place to prepare to join Augustus's stepson and senior military commander Tiberius in a war against the Germans. Instead, the Daesitiates mutinied and defeated a Roman force sent against them. The Daesitiates were soon joined by the Breuci led by Bato of the Breuci, another community inhabiting the region between the rivers Sava and Drava in modern Croatia. They gave battle to a second Roman force from Moesia led by Caecina Severus. Despite their defeat, they inflicted heavy casualties at the Battle of Sirmium. The rebels were now joined by a large number of other communities. At risk was the strategic province of Illyricum, recently expanded to include the territory of the Pannonii, an indigenous communities inhabiting the region between the rivers Drava and Sava, who were subjugated by Rome in 12–9 BC. Illyricum was on Italy's eastern flank, exposing the Roman heartland to the fear of a rebel invasion.
Augustus ordered Tiberius to break off operations in Germany and move his main army to Illyricum. Tiberius sent Marcus Valerius Messalla Messallinus ahead with troops. The panic broke out in Rome and Augustus raised a second task force under Tiberius's nephew Germanicus. He resorted to the compulsory purchase and emancipation of thousands of slaves in order to amass enough troops. This happened for the first time since the aftermath of the Battle of Cannae two centuries earlier. At one moment, in winter AD 6/7, 10 legions were deployed and an equivalent number of auxilia. In addition, they were assisted by a large number of Thracian troops deployed by their King Rhoemetalces I, a Roman amicus a grand total of some 100,000 men.
They faced further reverses on the battlefield and a bitter guerrilla war in the Bosnian mountains, but bitter fighting also occurred in southern Pannonia around Mons Almus near Sirmium. It took them three years of hard fighting to quell the revolt, which was described by the Roman historian Suetonius as the most difficult conflict faced by Rome since the Punic Wars two centuries earlier. Tiberius finally quelled the revolt in AD 9. This was just in time: that same year Arminius destroyed Varus's three legions in Germany. The Roman high command did not doubt that Arminius would have formed a grand alliance with the Illyrians.
The fighting of the Illyrian Revolt had lasting effects on Roman soldiers. Unhappy with their payment of swampy and mountainous Pannonian lands for such harsh military service, and with abuses relating to their pay and conditions, Roman soldiers staged a mutiny in AD 14 demanding recompense. Tiberius dispatched his son, Drusus, to pacify the mutineers.

Tactics and troop organization

Illyrians in ancient sources were known as brave and skilled fighters. The Illyrians appeared in war as free warriors under their rulers or kings. Similar to other societies the status of a leader was determined by the number of warriors who followed him. Obedience to a higher authority such as a king was channelled through the collective loyalty of a tribe to the chief. In historical sources they are described as a peasant infantry fighting under aristocratic proprietors each one controlling a town within the kingdom. The Dalmatians were known to use Partisan tactics against the Romans which were successful in inflicting serious defeats on the best of the Roman legions.
Diodorus Siculus writes of the Illyrian military formation in this battle that was an attempt for a coordinated stance by forming a square. His exact words are: "Ἰλλυριοὶ συντάξαντες ἑαυτούς εἰς πλινθίον ἐρρωμένος".

"But the Illyrians, forming themselves into a square, courageously entered the fray. And at first for a long while the battle was evenly poised because of the exceeding gallantry displayed on both sides, and as many were slain and still more wounded, the fortune of battle vacillated first one way then the other"

In the 2nd century BC the army of Agron and Teuta is no more represented in phalanxes but in smaller troops, armoured well and fast moving. These tactics also used in Roman times were ready for independent operations and so were more effective than earlier phalanxes. These exact tactics were agile for quick and surprising actions and soon showed to be superior against Greek tactics and as a result the Illyrians achieved victories over the Greeks.
On the sea the Illyrians used guerrilla tactics with their sophisticated navy. These sea tactics made the Illyrians masters of the Adriatic Sea for many centuries. Their ships, which were relatively small were not capable of direct naval battle with the heavier war-ships of the Greeks and Romans and most of the time were defeated. An exception is the victory over the island of Paxoi, where the Illyrians used a new form of tactic which involved connecting their ships in groups of four in order to attack Greek ships.

Weaponry

The fact that Illyrian warriors were buried with their weapons has resulted in an abundant amount of surviving intact. The works of ancient authors fail to provide a clear picture on Illyrian weapons and the only true contributor to this matter was the Roman poet Ennius who was of Messapian origin. Weaponry was very important to the Illyrians in the time of war however sometimes only the rich and nobles could afford some types such as greaves and helmets. A lot of armour was imported to mainly from the Greek mainland proved by the findings of Greek weapons in the Glacinac graves dating from the 7th century BC.
Shields were used among the Illyrians as early as the Bronze Age. In the Iron Age two types of shields were used, the Illyrian circular shield and the oval/rectangular type used by the northern Illyrians. The most common was the circular shield, which was made of wood and leather with a bronze boss and was like a mostly light pelte. The Illyrian circular shield resembled the Macedonian version but differed from the number of circular decortication. Their shapes with either round, rectangular or oval. A type of wooden oblong shield with an iron boss was introduced to Illyria from the Celts. This type of shield resembled the Illyrian oval shield used in northern Illyria.
Breast-armour and greaves were a speciality for the rich only in Illyrian society. Bronze breast-armor was used very rarely by the northern Illyrians and only three examples have been discovered so far in Slovenia. However another form of body armor was a bronze pectoral that may have protected part of the back as well. It was more like a disc "breastplate" of 10 cm in diameter. Greaves to protect the legs were used from the 7th century BC and probably even earlier. They first appeared in Illyria from its southern borders and are found only in princely graves.
In northern Illyria the bronze helmet was employed. The bronze helmet developed into the common Conical helmet which sometimes contained a plume. The most intriguing of all Illyrian helmets developed, the Shmarjet helmet, was made by the Japodes in the Lika valley. It was made from wicker and chain-mail while metal plates around the sides were optional. Under influence from Illyria's northern neighbours, the Italic peoples, the Negau helmet was used from the 5th century BC to the 4th century BC. The most widespread helmet was the Illyrian helmet with its use beginning from the 7th century BC. The Illyrian helmet was made from bronze and consisted of a great, crested plume on the top. The origin and the time period this helmet used has been a subject of much debate. Some experts allocate its origins in Corinth and claim it went out of use in Illyria in the 4th century BC. Others claim that the helmet has its origins in Illyria and that it was used up to the 2nd century BC, proven by depictions on Illyrian city coins of the time.
The principal sword of the Illyrians was the sica, a single-edged curved sword similar to the Greek machaira. The sica was developed during the Bronze Age. The sica's blade was about long. It became widely used and adopted by other peoples such as the Thracians, Dacians and the Romans. The Illyrians also used the fighting sword short curved swords, long swords in addition to various knives. According to historian John Wilkes:

Although a short curved sword was used by several peoples around the Mediterranean the Romans regarded the sica as a distinct Illyrian weapon used by the stealthy 'assassin'

The Illyrians also used a variety of other weapons, like javelins, long metallic spears called Sibyna that resembled boar spears, short thrusting spears, battle axes, single-handed axes that could be hurled and also bows and arrows which were used from the start of the 2nd millennium BC.

Mercenaries

Illyrians acted as mercenaries on several occasions whether on the side of the Greeks or the Romans. Perdiccas II of Macedon had hired Illyrian mercenaries in the 5th century BC but they betrayed him, allying with his enemy, Arrhabaeus of Lyncus. In another incident, Lysimachus killed all of his 5,000 Illyrian mercenaries to the last man, because he was convinced that they would join the enemy. Previously in 302 BC 2,000 of his Illyrian mercenaries had defected to Antigonus. Illyrians were not considered as reliable mercenaries, in the ancient world but were at the same time acknowledged as a skilled fighting force

Nobility

The nobility had access to breastplates and greaves whilst the bulk of the army did not. The kings did not resemble the rest of the army and were the only ones with full body protection which was a rarity. Illyrian kings and rulers wore bronze torques around their necks and were heavily armoured in antithesis to the bulk of their armies. A number of weapons and armaments were imported from Greece including helmets. Armaments were mostly made of bronze. Another form of body armour was a bronze pectoral. It was more like a disc "breastplate" of 10 cm in diameter. Local greaves made of bronze were strapped on the legs. Metal riveted belts were used as well.

Illyrian navy

The Illyrians were notorious sailors in the ancient world. They were great ship builders and seafarers. The most skilful Illyrian sailors were the Liburnians, Japodes, Delmatae and Ardiaei. The greatest navy was built by Agron in the 3rd century BC. The Illyrian tactics consisted of lashing their galleys together in groups of four and inviting a broadside attack from a ram. The Illyrians would then board the enemy craft in overwhelming numbers. Illyrian war ships were adopted by many peoples especially the Greeks and Romans. Illyrian craftsmen were even hired by the King of Macedon to build 100 ships in the First Macedonian War because to him they bore a special gift of ship building. The earliest evidence of Illyrian ships is from the design of a ship incised on bronze greaves from Glasinac dating from the 8th century BC to the 7th century BC. The front of this ship is constructed in the form of an animal probably a horse.
Illyrian ships were a favourite depiction on Illyrian coins especially on the coinage of the Labatae. The type of war ships presented on the coins is hard to determine. However, all the depictions show a similarity in which the bows of the ships were shaped in the form of a serpents head. The Byzantine author from the 6th century wrote that the Adriatic was a sea in which serpents swam.
The Liburnians were renowned seafarers dominating the Adriatic and Ionian Sea from the start of the 1st millennium to the 5th century BC. The Romans knew them principally as a people addicted to piracy. The major harbour of Liburnian navy since the 5th century BC was Corynthia at eastern cape of Krk island, including 7 unearthed docks, marine arsenal, and stony fortifications; this early harbour persisted in ancient and medieval function to the 16th century. Liburnians constructed different ship types; their galaia was an early prototype of transport galleys, lembus was a fishing ship continued by the actual Croatian levut, and a drakoforos was apparently mounted with a dragon head at the prow. Remains of a 10 meters long ship from the 1st century BC, were found in Zaton near Nin, a ship keel with bottom planking made of 6 rows of the wooden boards on each side, specifically joined together, sewn with resin cords and wooden wedges, testifying the Liburnian shipbuilding tradition style, therefore named "Serilia Liburnica". Deciduous trees were used, while some climber was used for the cords.
The Illyrians were often referred to as pirates, raiding Greek and Roman vessels. Illyrian's indulgence in piracy was one that brought them infamy and invited their downfall. Their rugged broken coast with its screen of islands formed a perfect base from which their light and speedy little to attack unwary ships. The Illyrians piratical career reached its zenith under Queen Teuta. The Illyrians practised boarding tactics against enemy vessels. Although this view was widely accepted at first this connection is not completely true. Ancient Greek and Roman authors often attacked Illyrians in their works merely because they saw them as enemies and so many sources may be heavily exaggerated.
The three main types of Illyrian warships were the Lembus, the Liburna and the Pristis.

Lembus

The lembos, was an ancient Illyrian warship, with a single bank of oars and no sails. It was small and light, with a low freeboard. It was a fast and manoeuvrable warship capable of carrying 50 men in addition to the rowers. It was most commonly associated with the vessels used by the Illyrian tribes, chiefly for piracy, in the area of Dalmatia. This type of craft was also adopted by Philip V of Macedon, and soon after by the Seleucids, Rome, and even the Spartan king Nabis in his attempt to rebuild the Spartan navy.
In contemporary authors, the name was associated with a class rather than a specific type of vessels, as considerable variation is evident in the sources: the number of oars ranged from 16 to 50, they could be one- or double-banked, and some types did not have a ram, presumably being used as couriers and fast cargo vessels.

Liburna

The most known Liburnian ship was their warship, known as a libyrnis to the Greeks and a liburna to the Romans, propelled by oars. According to some thoughts, liburna was shown in the scene of naval battle, curved on a stone tablet found near Antique Pisaurum, outlined to 5th or 6th century BC, the most possibly showing imaginary battle between Liburnian and Picenian fleets. Liburna was presented as light type of the ship with one row or the oars, one mast, one sail and prow twisted outwards. Under the prow there was a rostrum made for striking the enemy ships under the sea.
By its original form, the Liburna was the most similar to the Greek penteconter. It had one bench with 25 oars on each side, while in the late ages of the Roman Republic, it became a smaller version of a trireme, but with two banks of oars, faster, lighter, and more agile than biremes and triremes. The Liburnian design was adopted by the Romans and became a key part of Ancient Rome's navy, most possibly by mediation of Macedonian navy in the 2nd half of the 1st century BC. Liburna ships played a key role in naval battle of Actium in Greece, which lasted from August 31 to September 2 of 31 BC. Because of its naval and manoeuvrer features and bravery of its Liburnian crews, these ships completely defeated much bigger and heavier eastern ships, quadriremes and penterames. Liburna was different from the battle triremes, quadriremes and quinqueremes not because of rowing but rather because of its specific constructional features. It was long and wide with a draft. Two rows of oarsmen pulled 18 oars per side. The ship could make up to 14 knots under sail and more than 7 under oars. Such a vessel, used as a merchantman, might take on a passenger, as Lycinus relates in the 2nd-century dialogue, traditionally attributed to Lucian of Samosata: "I had a speedy vessel readied, the kind of bireme used above all by the Liburnians of the Ionian Gulf."
Once the Romans had adopted the Liburnian, they proceeded to make a few adaptations to improve the ships’ use within the navy. The benefits gained from the addition of rams and protection from missiles more than made-up for the slight loss of speed. Besides the construction, the ships required that the regular Roman military unit be simplified in order to function more smoothly. Each ship operated as an individual entity, so the more complicated organization normally used was not necessary. Within the navy, there were probably Liburnian of several varying sizes, all put to specific tasks such as scouting and patrolling Roman waters against piracy. The Romans made use of the liburnian particularly within the provinces of the empire, where the ships formed the bulk of the fleets, while it was included by small numbers in fleets of Ravenna and Micenum, where a large number of the Illyrians were serving, especially Dalmatae, Liburnians and Pannonians.
Gradually liburna became general name for the different types of the Roman ships, attached also to the cargo ships in the Late Antique. Tacitus and Suetonius were using it as a synonym for the battle ship. In inscriptions it was mentioned as the last in class of the battle ships: hexeres, penteres, quadrieres, trieres, liburna.
In the Medieval sources the "liburna" ships were often recorded in use by the Medieval Croatian and Dalmatian pirates and sailors, but probably not always referring to the ships of the same form.

Pristis

The Pristis was a beaked long and narrow war ship

Fortifications

Illyrians built hill-forts as places of refuge such as Tilurium and Setovia of the Delmatae. Most enclosures were round or oval with very few exceptions for other shapes and the largest two were 200 meters across while most are not anything more than fortified blockhouses.
The Castellieri were fortified boroughs, usually located on hills or mountains or, more rarely, in plains. They were constituted by one or more concentric series of walls, of rounded or elliptical shape in Istria and Venezia Giulia, or quadrangular in Friuli, within which was the inhabited area. Some a hundred of castellieri have been discovered in Istria, Friuli and Venezia Giulia, such as that of Leme, in the central-western Istria, of the Elleri, near Muggia, of Monte Giove near Prosecco and San Polo, not far from Monfalcone. However, the largest castelliere was perhaps that of Nesactium, in the southern Istria, not far from Pula.

External influences

Hellenistic influence

The graves of Illyrian nobles contained a great number of Greek imports including weaponry. This includes finds at Glasinac, Lake Ohrid in North Macedonia, Dolensko in Slovenia and various sites in Albania. The Glasinac culture encompasses eastern Bosnia, south-western Serbia, Montenegro and northern Albania. Ancient Greek Illyrian type helmets either as imports or later copies had spread throughout Illyria and one was found as far as Slovenia not only in the Glasinac cultural area like the helmet found in the grave at Klicevo, Montenegro. The Greek helmets found in some of these sites were of "type I" and very few of "type II".
Illyrians on the coast of the Adriatic were under the effects and influence of Hellenisation due to their proximity to the Greek colonies in Illyria. Apart from other cultural influences and imported weapons and armour from the Ancient Greeks the Illyrians had adopted the ornamentation of Ancient Macedon on their shields and used similar designs on bracelets. The Illyrians used four concentric half circles whilst the Macedonians five. This ancient Greek symbol was prominent in Thessaly and Macedon, appearing in the 10th century BC and had spread throughout southern Greece. A typical adoption of the symbol in the Hellenistic period from Illyrians is seen on an iron round pelte with similar decorations and a diameter of 35 cm. This is evident during the Greek rule of south Illyria the Antipatrid dynasty & the Antigonid dynasty retained until the Roman conquest. Tactics had been influenced as well, evident in an incident involving Dardanians. The Hellenised city of Daorson located in Dalmatia included "cyclopean walls".

Roman

Illyria became a Roman province at 168 BC. The Illyrians, that were eventually Romanized rebelled in AD 6. Nearly two hundred years of Roman rule changed the weapons of the Illyrians by the time of the rebellion and they resembled those of Roman legionaries. The tribes that rebelled had been Celticized by the time Romans conquered Illyria in 168 BC and their equipment reflected this. Inhabitants of Roman Dalmatia applied a poison on their arrows called ninum. This was not a Roman influence but was mentioned during that time.

Timeline

Collapse of southern Illyrian nations and the start of Roman campaigns against Illyrian interior