General
Population: Between 190 and 230 million*
- Religion: Boniface "apostle to the Germans" born
- Technology: Greek Fire first used at Battle of Cuzicus by Syrians
- Deaths: Childeric II of Austrasia
Europe
- England: First Synod of English church at Hertford
Founding of Ely abbey
- Franco-German States: Death of Childeric II of Austrasia – civil war and anarchy plague Frankish kingdom
- Italian States: Saraceans launch fleet against Romans
Middle East
- Byzantine Empire: Arabs besiege Constantinople until 678 without success - Start of Moslem-Byzantine Wars