Shimazu Tadatsune, Japanese daimyō (born 1576)

Shimazu Tadatsune was a tozama daimyō of Satsuma, the first to hold it as a formal fief (han) under the Tokugawa shogunate, and the first Japanese to rule over the Ryūkyū Kingdom. As lord of Satsuma, he was among the most powerful lords in Japan at the time, and formally submitted to Tokugawa Ieyasu in 1602, to prove his loyalty, being rewarded as a result with the name Matsudaira Iehisa; Matsudaira being a branch family of the Tokugawa, and "Ie" of "Iehisa" being taken from "Ieyasu", this was a great honor. As of 1603, his holdings amounted to 605,000 koku.