The Sano clan was a branch of the Oyama clan, who settled in Sano shōen during the Kamakura period, and who ruled the area over 15 generations from their impregnable mountain stronghold of Karasawayama Castle. The area was contested during the Sengoku period between the forces of the Uesugi clan and the Odawara Hōjō clan, and Karasawayama Castle withstood ten attempts to conquer it by the famed warlord Uesugi Kenshin. The 17th generation head of the Sano clan, Sano Munetsuna was defeated by Nagao Akinaga, but the Sano territories were restored by Toyotomi Hideyoshi in recognition of their efforts at the 1590 Battle of Odawara. After Tokugawa Ieyasu took control over the Kantō region in 1592, he confirmed Sano Nobuyoshi as daimyō of a 35,000 koku holding. This was the start of Sano Domain. However, the Sano clan was dispossessed of their holdings in 1614 for reasons which are still unclear. During the time of Shōgun Tokugawa Ietsuna, Sano Domain was revived as a 10,000 kokusubsidiary holding of Sakura Domain for Hotta Masataka, the third son of the TairōHotta Masatoshi. The Hotta built a modestjin'ya from which to rule the domain in line with its minor status. However, when Hotta Masataka was relocated to Katada Domain in Omi Province in 1698, the domain lapsed back to tenryō status. The 4th generation descendant of Hotta Masatoshi, Hotta Masaatsu, relocated from Katada back to Sano in 1826, where his descendants continued to reside to the end of the Tokugawa shogunate. The domain was quick to support the pro-imperial cause in the Boshin war of the Meiji restoration. After the abolition of the han system in July 1871, Sano Domain became part of Tochigi Prefecture. The domain had a population of 11,893 people in 2516 households, of which 1101 were samurai in 230 households per a census in 1870.
Holdings at the end of the Edo period
As with most domains in the han system, Sano Domain consisted of several discontinuous territories calculated to provide the assigned kokudaka, based on periodic cadastral surveys and projected agricultural yields. Due to its history, the majority of its territory was in Omi Province.