Original sentence: A year later, he was accidentally struck in the head by a sword-swipe; the blow left him mentally incapacitated until his resultant death in 866
Edited sentence: A year later, he was accidentally struck in the head by a sword-swipe in a mock combat.Halsall, Guy.London:  Routledge, 2003.The blow, inflicted by a member of his own hunting party (leading Ado of.Vienne to say "Charles was dishonoured (dehonestatus) by having suffered it"), left him mentally incapacitated until his resultant death in 866.Warfare and Society in the Barbarian West, 450-900