John I Tzimiskes

John I Tzimiskes (c. 925–976) was an Armenian-born Byzantine commander who helped murder his uncle Nikephoros II in 969 and seized the crown. He crushed Bardas Phokas's revolt. In 971 he besieged Sviatoslav of Kiev at Dorostolon for sixty-five days, negotiated the departure of the Rus', and proclaimed Bulgaria annexed. On his return to Constantinople he stripped Boris II of his imperial insignia.

In 972–975 he campaigned through Mesopotamia and Syria, but failed to take Jerusalem. He died on his return in 976, supposedly poisoned by Basil Lekapenos, and Basil II succeeded him.