During the Sengoku period, the area around Gujō was controlled by the Endō clan, who pledged fealty to Oda Nobunaga, followed by Toyotomi Hideyoshi. Under Hideyoshi, they were reduced to serve under the Inaba clan; however, following the Battle of Sekigahara, the Inaba were transferred to Usuki Domain in Bungo Province, and the Endō clan was restored to their former territories, becoming daimyō of the 27,000 koku Gujō Domain from 1600 to 1693. The 3rd Endō daimyō, Endō Tsunetomo reduced the domain to 24,000 koku by giving 2,000 koku and 1,000 koku holdings to two of his younger brothers, but was successful in elevating his official status to that of a “castellan”. His successor, Endō Tsuneharu faced problems with peasant revolts, and his successor, Endō Tsunehisa was a minor, and died of poisoning soon after taking office. However, the Endō clan escaped attainder, and were transferred to the 10,000 kokuMikami Domain in Shimotsuke Province, where they resided to the Meiji restoration.[2]
The Inoue were transferred to Kameyama Domain in Tanba Province in 1697 and were replaced by the Kanemori clan from Kamiyama Domain in Mutsu Province from 1697 to 1758 with a kokudaka set at 38,000 koku.[1] The Kanemori faced a 4-year peasant revolt from 1754 which they were unable to suppress, and they were removed from office by the Tokugawa shogunate.
In 1758, the shogunate entrusted Gujō to the Aoyama clan, formerly of Miyazu Domain in Tango Province, with a kokudaka of 48,000 koku. The Aoyama ruled until the Meiji restoration.[1] During the Boshin War, the domain contributed its military forces to the Satchō Alliance, although many of its samurai defected to the Tokugawa side.
As with most domains in the han system, Gujō Domain consisted of a discontinuous territories calculated to provide the assigned kokudaka, based on periodic cadastral surveys and projected agricultural yields.[3][4]