Plan of the Osaka Second or Summer Campaign, 1615', 1903. The siege of Osaka was a series of battles by the Tokugawa shogunate against the Toyotomi clan. During the summer of 1615, Ieyasu fought many battles, ultimately Toyotomi Hideyori's commander Sanada Yukimura was killed, Osaka castle was set on fire and up to 10,000 people are said to have died. From 'A History of Japan during the century of early foreign intercourse' (1542-1651) by James Murdoch, M.A. and Isoh Yamagata. [Kobe, Japan, 1903]