August Zaleski was born in Warsaw on 13 September 1883. In 1901 he graduated from a gymnasium in Praga and became a librarian for the Krasiński family, but finally moved to London, where he received a master's degree from the London School of Economics. He was unable to return to Poland during World War I and, in 1917, started lecturing in the Polish language in London. About that time he also became interested in freemasonry and became one of the collaborators of the Polish National Committee, the institution that was to become the Polish representative to the Triple Entente. As such, he was one of Roman Dmowski's envoys to assure English politicians that Józef Piłsudski's Polish Legions had sided with the Central Powers in order to combat Russia, not the West. In 1918, when Poland regained her independence, Zaleski proved to be a skilled diplomat and served at various posts in Polish embassies in Switzerland, Greece, Italy and was one of the Polish envoys to the League of Nations. After the May Coup d'État of 1926 he sided with the camp of Marshal Józef Piłsudski and, until 1932, held the post of minister of foreign affairs in two subsequent governments. In June 1932, Zaleski was visiting a session of the League of Nations in Geneva when found he thrust into the middle a crisis in Danzig when he learned that the destroyer ORP Wicher had been sent into the harbour of the Free City of Danzig without the permission of the Senate of the Free City. Through Zaleski had not been informed that the Wicher was going to Danzig, he put up an able defense of Poland at the League Assembly and Council. In talks with the Secretary-General Sir Eric Drummond, Zaleski offered the promise that Poland would not send the Wicher back to Danzig at a time when the German battleship Schlesien was scheduled to visit, a confrontation that would potentially cause a German-Polish war in exchange for which Zaleski wanted the League to pressure the Free City to resolve the port d'attache issue governing the right of the Polish Navy to use Danzig harbour resolved in a manner satisfactory to Poland. Zaleski's offer was taken and Drummond successfully pressured the Free City into settling the port d'attache issue in a manner favorable to Poland. Between 1928 and 1935, Zaleski was also a member of the Senate of Poland. At the end of his term, he retired from active politics and became chairman of Bank Handlowy, one of the best-known Polish banks of the time. He held that post until the invasion of Poland, when he successfully evacuated his company's assets first to France and then the United Kingdom. In exile, August Zaleski yet again became minister of foreign affairs, this time in the government of General Władysław Sikorski. In June 1947, Zaleski was nominated president of Polish government in exile. Initially supported by much of the Polish diaspora, he nominated General Tadeusz Bór-Komorowski to be prime minister. However, by the end of his seven-year term, Zaleski was facing opposition and was at odds with much of the political elite. His response was to extend his term and nominate Stanisław Cat-Mackiewicz to be prime minister. Many Poles in exile considered this unlawful and therefore created the Council of the Three, a collective head of state that was to take over the role of the president of Poland until Zaleski properly resigned his post. However, in fact for almost twenty years the Council and Zaleski claimed the position simultaneously. August Zaleski died in London on 7 April 1972. Among his papers, two conflicting nominations of his successor were found: one naming Stanisław Ostrowski and the other one, perhaps forged, naming Juliusz Nowina-Sokolnicki. The Council of the Three accepted the former and disbanded.
