Caedwalla (c. 659 - April 20, 689) was a King of Wessex (685 - 688). During his brief reign, he conquered the southeast of England.
Caedwalla was the son of Cenberht, a West Saxon sub-king who had been killed during a Mercian invasion in 661. In 685, apparently acting as an independent warlord, he conquered Sussex, killing its king Athelwalh. Possibly he intended to make it his own kingdom, but in any case he was quickly expelled by a rebellion under Berthun.
Later in the same year, King Centwine of Wessex abdicated to become a monk and Caedwalla took his place; it is possible that he had forced Centwine's retirement. In 686, he again attacked Sussex, killed Berthun and firmly established West Saxon authority there. He subsequently marched on into Kent, where he killed its king Eadric and set up his own brother Mul as a client king.
In 687, Caedwalla attacked the Isle of Wight, which was still an independent pagan kingdom. There he waged a brutal campaign of slaughter against the inhabitants, and their last king, Arwald, died fighting. Caedwalla himself did not escape unscathed, however: he was badly wounded, and in 688 he was formally converted to Christianity by Saint Wilfrid.
By this time, the people of Kent had risen in rebellion against Mul, cornered him in a house and burned him alive. Caedwalla responded with a renewed campaign against Kent, laying waste to its land and leaving it in a state of chaos. At this point, however, Caedwalla was dying of his wounds. He abdicated and went on a pilgrimage to Rome, where he was baptized by Pope Sergius I on April 10, 689. He died ten days later.