721

Byzantine Empire

 * Former emperor  leads a revolt against emperor

Europe

 * succeeds
 * —, the governor (al-Andalus) is defeated by Duke  preventing an Arab invasion of.
 * is appointed governor of
 * Legendary founding of by the Princess  and her husband, founder of the dynasty with the same name.

China

 * Rains and heavy storms around the southern seaport of reportedly destroyed over 1,000 ships and boats in the usual congested canal and river traffic of the  era.

Births

 * (a.k.a. Geber), Arabian (approximate date)
 * , first  (d. )

Deaths

 * , (–721) and presumed author of the
 * , Chinese chancellor of the (born )
 * , Chinese historian (born )
 * , Chinese historian (born )