Basil II (958?-1025), Byzantine emperor (976-1025), the greatest ruler of the
Macedonian dynasty. The son of Emperor Romanus II, he reigned jointly with his
brother Constantine VIII after the death of the usurper John I Tzimisces in
976, but Constantine never took an active role in government. Basil's greatest
achievements were the conquest of Armenia in the east and the destruction of
the Bulgarian Empire, which threatened Byzantium on the west. He waged war on
the Bulgars for nearly two decades. Defeating (1014) the Bulgarian czar
Samuel, he subjected his people to Byzantine rule and was given the surname
Bulgaroctonos (Slayer of Bulgars). The Byzantine Empire began to decline after
Basil's death.