The New Student's Reference Work/Vladimir the Great

Vladimir (vlăd′ ĭ-mḗr) the Great, a Russian ruler, who reigned from 980 to 1015.  He added largely to the kingdom by conquest, but is best known for the introduction of Christianity into the Empire.  He embraced the doctrines of the Greek church, and was baptized at Constantinople in 988, the day after his marriage to the sister of the Byzantine emperor.  He died in 1015.