Peter of Kiyv was an Eastern Orthodox bishop who served as the Metropolitan of Kiev and all Rus' during the early 14th century. Born in Volhynia around 1260, he entered a monastery at age twelve and later lived as an ascetic near the Rata River. After being appointed to the vacant see of Kiev in 1308, he eventually moved his seat from Vladimir to Moscow in 1325 at the request of Grand Prince Ivan Kalita. This strategic relocation helped establish Moscow as a major spiritual center.