The Emperor's role had been usurped by the Minamoto and Hōjō families ever since Minamoto no Yoritomo had obtained from the Emperor the title of shōgun in 1192, ruling thereafter from Kamakura.[1] For various reasons, the Kamakura shogunate decided to allow two contending imperial lines—known as the Southern Court or junior line, and the Northern Court or senior line—to alternate on the throne.[2] The method worked for several successions until a member of the Southern Court ascended to the throne as Emperor Go-Daigo.[2] Go-Daigo wanted to overthrow the shogunate and openly defied Kamakura by naming his own son his heir.[2] In 1331 the shogunate exiled Go-Daigo but loyalist forces, including Kusunoki Masashige, rebelled and came to his support.[2] They were aided by, among others, future shōgun Ashikaga Takauji, a samurai who had turned against Kamakura when dispatched to put down Go-Daigo's rebellion.[2] At roughly the same time, Nitta Yoshisada, another eastern chieftain, attacked the shogunate's capital. The shogunate tried to resist his advance: Yoshisada and shogunate forces fought several times along the Kamakura Kaidō, for example at Kotesashigahara (小手差原), Kumegawa (久米河) (both near today's Tokorozawa, Saitama Prefecture), and Bubaigawara, in today's Fuchū, ever closer to Kamakura. The city was finally reached, besieged, and taken.