In 1351 in the middle of the Kano Disturbance, Takauji ASHIKAGA, seii taishogun (literally, "great general who subdues the barbarians") of the Muromachi bakufu (Japanese feudal government headed by a shogun), surrendered Emperor Gomurakami of Southern Court; in response to this, the Southern court army conquered Kyoto, and held the imperial family members on the Northern court side in custody.
ところが、観応の擾乱の最中の1351年（観応2年/正平6年）、室町幕府の征夷大将軍である足利尊氏が南朝の後村上天皇に降伏、これを受けて南朝軍が京都を制圧して北朝方皇族を拘禁した。