Katsura Tarō
From 1900 to 1909, Yamagata opposed Itō Hirobumi, leader of the civilian party, and exercised influence through his protégé, Katsura Tarō. After the assassination of Itō Hirobumi in 1909, Yamagata became the most influential statesman in Japan and remained so until his death in 1922, although he retired from active participation in politics after the Russo-Japanese War. As president of the Privy Council from 1909 to 1922, Yamagata remained the power behind the government and dictated the selection of future Prime Ministers until his death. However, his power was greatly damaged in 1921 when he expressed strong opposition to the engagement of Hirohito and Nagako citing color blindness of Nagako's family. The Imperial family struggled against the pressure from Yamagata and the couple eventually managed to get married.