The practice of enfeoffment of local spirits has a long history in Vietnam, and became particularly widespread under the Nguyên Dynasty (1802-1945). Legitimacy was one of the major concerns of the Nguyên emperors. Enfeoffment served not only to legitimize local cults in the eyes of the court, but more importantly to provide the rulers with a sort of spiritual legitimacy at the local level. The certificates were supposed to be confirmed by each successive ruler. It is unlikely that any certificates were issued during the four brief reigns of 1883-1885. The custom may have been allowed to lapse under Bao Dai (r. 1925-1945).