Description: (King)
Boris I of Bulgaria, known as Saint Boris I, ruled the First Bulgarian Empire from 852 to 889. His reign was marked by key events including the Christianization of Bulgaria in 864, the establishment of the autocephalous Bulgarian Church, and the promotion of the Cyrillic script and Slavic literature. Boris I successfully managed conflicts between the Patriarchate of Constantinople and the Papacy to safeguard Bulgaria's independence. His initiatives resulted in the substitution of Byzantine clergy with Bulgarian clergy and the use of Old Church Slavonic in Preslav.