Though the youngest of his parents' nine children, Kiyochika took over as head of the household upon his father's death in 1862 and changed his name from Katsunosuke. As a subordinate to a "kanjō-bugyō" official Kiyochika travelled to Kyoto in 1865 with Tokugawa Iemochi's retinue, the first shogunal visit to Kyoto in over two centuries. They continued to Osaka, where Kiyochika thereafter made his home. During the Boshin War in 1868 Kiyochika participated on the side of the shōgun in the Battle of Toba–Fushimi in Kyoto and returned to Osaka after defeat of the shōgun's forces. He returned by land to Edo and re-entered the employ of the shōgun. After the fall of Edo he relocated to Shizuoka, the heartland of the Tokugawa clan, where he stayed for the next several years.