His achievement as emperor from 976 was to contain, and later decisively defeat, the Bulgarians, earning for himself the title "Bulgar-slayer" after a victory in 1014. After the battle he blinded almost all 15,000 of the defeated, leaving only a few men with one eye to lead their fellows home (very gentle and considerate, don't you think?). At the time of his death the Byzantine empire reached its greatest extent.