Realizing that he was at the end of his rope, the Emperor fled from Kyoto for Kasagi, and was besieged there by Kamakura Shogunate troops (Godaigo would survive the siege but would be banished to the Isles of Oki).

[4]: 13–14 [5]: 174 During the initial assault by the Kamakura force, Masashige used skilled archers to kill or wound many before they retreated hastily to make camp for a longer siege.

Kusunoki Shichiro picked this time to attack the camp with his horsemen from two sides, and was soon joined by more cavalry from the castle gates.

As the Kamakura troops hit the ground, Masashige's force subjected them to logs and stones hurled at them from within the fortress, inflicting grievous harm.

In an attempt to finally break the siege, Masashige devised a plan in which his men disguised themselves as Shogunate soldiers and left the bodies of the slain combatants in the fort in a large pile of kindling.

[citation needed] After retaking Lower Akasaka, he built Kami-Akasaka upon a small plateau surrounded on three sides by a low valley.