Battle of Arcadiopolis: John I dispatches an elite force (10–12,000 men) to delay the Kievan Rus'. The Byzantines under Bardas Skleros successfully ambush the Kievan-Bulgarian invaders at Arcadiopolis (modern Turkey). The battle turns into a complete rout, killing thousands. Grand Prince Sviatoslav I is driven out of Thrace and withdraws his forces to the fortress city of Silistra.[2]
Summer – Bardas Phokas (the Younger) and his family rebel against their own cousin, John I. Bardas is proclaimed 'emperor' by his troops at Caesarea, but the rebellion is extinguished by Bardas Skleros. Phokas and his relatives are captured and exiled to the island of Chios (Aegean Sea).
Europe
Summer – Byzantine-Imperial truce: Emperor Otto I (the Great) meets with John I at Bari and accepts a permanent peace agreement. Pandulf I (Ironhead) is released from captivity in Constantinople (see 969).
The oldest preserved document (by Otto I) mentions Leibnitz in Styria (modern Austria).