In 1614 (Keicho 19), Tokugawa Ieyasu besieged Osaka Castle (present-day Osaka City, Osaka Prefecture), the stronghold of Toyotomi Hideyori. Using the inscription on the bell of Hoko-ji Temple as a pretext, Ieyasu declared his intention to subjugate the Toyotomi clan and surrounded Osaka Castle with an army of over 200,000 troops. The Toyotomi forces constructed the Sanada-maru — an outer defensive…

In October 1614, Tokugawa Ieyasu declared a campaign against the Toyotomi clan, using a dispute over the inscription on a bell at Hōkōji Temple as a pretext, thus beginning the Siege of Osaka (Winter Campaign). Ieyasu mobilized a force exceeding 200,000 troops and surrounded Osaka Castle, where Toyo…