Sō clan
Tsushima Province had been controlled by the Tsushima no Kuni no miyatsuko until the Heian period. This clan was later replaced by the Abiru clan. The Sō clan rose to power around the middle 13th century and seized control of the entire island in the late 15th century. During the Edo period, Tsushima Province was dominated by the Tsushima-Fuchū Domain (Izuhara domain) of the So clan. It was put in charge of diplomacy and monopolized trade with the Joseon dynasty of Korea.