On August 18, 1863 the Aizu and Satsuma clans took control of the gate of the Imperial court, and carried out a coup forcing the Choshu clan and seven nobles, including Sanjo, to retreat to Choshu, successfully crushing the power of those sonjo party related to the Choshu clan (Coup of August 18, the exile of the seven nobles from Kyoto).
文久3年8月18日、宮廷の御門を制圧した会津・薩摩は、長州藩兵および三条ら7人の公卿を長州への撤退させるクーデタを決行し（八月十八日の政変、七卿落ち）、長州藩系の尊攘勢力の一掃に成功した。