生麦事件
In 1862, Hisamitsu went to Kyoto, and took part in the increasingly Kyoto-centered politics of the 1860s; he was a part of the "kōbu-gattai" political faction. It was during Hisamitsu's return from a stay in Edo, when three Englishmen on horseback offended his retainers by refusing to dismount or stand aside. Their failure to observe proper etiquette resulted in some argument, a chase, and one was killed, in what came to be known as the Namamugi Incident. Hisamitsu remained at the core of the "kōbu-gattai" movement in Kyoto, until Satsuma's secret alliance with men of Chōshu. He supported the Satsuma domain's military actions in the Boshin War, and retired soon after the Meiji Restoration. In the Meiji era, he was given the rank of duke (), the highest of the newly-created "kazoku" nobility and which was awarded for his clan's participation during the Restoration. Hisamitsu died in December 6,1887, at age 70. He was accorded a state funeral.