Toyotomi Hideyori ( September 8, 1593 - June 5, 1615) was the son and designated successor of Toyotomi Hideyoshi, the general who first united all of Japan. His mother, Yodo-dono, was the niece of Oda Nobunaga. When Hideyoshi died in 1598, the regents he had appointed to rule in Hideyori's place began jockeying amongst themselves for power. Tokugawa Ieyasu seized control in 1600, after his victory over the others at the Battle of Sekigahara. Tokugawa forces attacked Hideyori in the Siege of Osaka in the winter of 1614. The attack failed, but Hideyori was induced to sign a truce and dismantle the defenses of his stronghold Osaka Castle. In April 1615, Ieyasu received word that Toyotomi Hideyori was gathering even more troops than in the previous November, and that he was trying to stop the filling of the moat of Osaka Castle. Toyotomi forces (often called the Western Army) began to attack contingents of the Shogun's forces (the Eastern Army) near Osaka. On June 5, 1615, as Toyotomi's fo