The Retired Emperor Uda who learned from the Ako Incident did not desire the birth of a prince whose maternal grandfather was from the main branch of the Northern House of the Fujiwara clan, and intended to install a son of Tameko as a Crown Prince.
宇多上皇は阿衡事件の教訓から藤原北家嫡流を外祖父とする皇子の出生を望まず、為子所生の男子を立太子する方針であった。