Sō

The Sō were lords of Tsushima Island, where they rose as deputies of the Shōni clan in the Kamakura period. Sō Sukekuni died fighting the Mongol invasion in 1274, and Sō Sumishige became governor of Tsushima in 1395.

Toyotomi Hideyoshi confirmed the family's possession of Tsushima in 1587. Sō Yoshitoshi led troops against Busan in the invasion of Korea in 1592; after the war, the Tokugawa shogunate entrusted the family with negotiations and trade with Joseon. The Sō continued to rule the Tsushima-Fuchū domain throughout the Edo period.