Osaka Castle was built by Toyotomi Hideyoshi in 1583 as his principal stronghold.
Hideyoshi began construction on the site of Ishiyama Hongan-ji, a fortified temple complex that Oda Nobunaga had destroyed. The castle was intended to display Hideyoshi’s authority and provide a powerful base after he succeeded Nobunaga as Japan’s leading warlord.
The original complex was exceptionally large and richly decorated. Hideyoshi’s son, Toyotomi Hideyori, later occupied it, and the castle became the center of resistance to Tokugawa Ieyasu. Tokugawa forces captured Osaka Castle during the Winter and Summer campaigns of 1614–1615, ending Toyotomi rule.
The present main tower is a twentieth-century concrete reconstruction, not the surviving original keep. The castle is therefore historically important both as Hideyoshi’s power center and as the final stronghold of the Toyotomi family.