Kurobane Domain

 was a feudal domain under the Tokugawa shogunate of Edo period Japan, located in the Nasu District of Shimotsuke Province (modern-day Tochigi Prefecture), Japan. It was centered on Kurobane "jin'ya" in what is now part of the city of Ōtawara, Tochigi. Kurobane was ruled through all of its history by the "tozama" Ōzeki clan.
History.
After Tokugawa Ieyasu took control over the Kantō region in 1590, he assigned a 13,000 "koku" holding in northern Shimotsuke Province to Ōzeki Takamasu, the head of one of the seven leading samurai clans from the area. His son, Ōzeki Sukemasu, fought a rear-guard action against the Uesugi clan in Aizu during the Battle of Sekigahara and was rewarded with an increase in "kokudaka" to 20,000 "koku" and was confirmed as "daimyō" of Kurobane.
Although their residence was styled as a "jin'ya", it was built in the former central bailey of the clan’s ancestral Kurobane Castle, which was located on a 50-meter tall hill, with moats, earthen ramparts and "yagura" watchtowers.
During the time of the 4th "daimyō", Ōzeki Masuchika, the domain was divided, with 1000 "koku" going to each of his two younger brothers. In 1689, the noted haiku poet Matsuo Basho spent 14 day at Kurobane while traveling the Tohoku region and writing the "Oku no Hosomichi". This was the longest stay in any one location during his journey. The 15th "daimyō", Ōzeki Masuhiro, served in a number of important posts within the Bakumatsu period Tokugawa shogunate, including "Kaigun bugyō" and "wakadoshiyori". He also improved the domain’s military by introducing the Spencer repeating rifle and western military technologies. The 16th and final "daimyō", Ōzeki Masatoshi, sided with the Satchō Alliance in the Boshin War of the Meiji Restoration, and fought in the Battle of Aizu.
After the abolition of the han system in July 1871, Kurobane Domain became part of Tochigi Prefecture. 
The domain had a population of 19,493 people in 3666 households, of which 1937 were samurai in 638 households per a census in 1870. 
Holdings at the end of the Edo period.
As with most domains in the han system, Kurobane Domain consisted of several discontinuous territories calculated to provide the assigned "kokudaka", based on periodic cadastral surveys and projected agricultural yields. 