The Consecration of the Church of the Great Martyr George at Kiev: Beginning with the holy Prince Vladimir (July 15), it was the pious custom of Russian princes to build a church in honor of their patron saint. Thus, St Vladimir (in Baptism Basil) built at Kiev and Vyshgorod temples dedicated to St Basil the Great (January 1).
Prince Izyaslav I (1054-1068) (in Baptism Demetrius) built a church and monastery at Kiev in the name of the Holy Great Martyr Demetrius (October 26). Prince Yaroslav the Wise (in Baptism George) started to build a church and men's monastery in honor of his patron saint, the Holy Great Martyr George (April 23). He also built a church named for his wife's patron saint, the Holy Great Martyr Irene (May 5). The temple in honor of the Great Martyr George was consecrated by St Hilarion, Metropolitan of Kiev (October 21), and a yearly commemoration was established in honor of this event. SOURCE: