Constantine III (d. 411). Usurper, proclaimed emperor by Roman troops in Britain. At the beginning of the 5th cent. ad Roman Britain was not heavily defended, Stilicho having withdrawn troops in 401–2 to help defend Italy against German invaders. This attack on Italy and the overrunning of Gaul by Germanic tribes left Britain as an isolated and relatively untroubled area from which came three successive attempts to usurp power. In ad 406 Marcus seized power in Britain, but after a few months was replaced by the equally short-lived Gratian. The new usurper, Constantine III, was more effective, managing to take substantial territories in Gaul and Spain, and enjoying some moderate successes against the Germans. Eventually he was defeated by the forces of the western emperor Honorius: in 411 he was besieged at Arles, captured, and executed.

Eleanor Scott

Constantine III (d. 997), king of ‘Scotland’ (from 995). He reigned for only a year and a half following the assassination of Kenneth II. He was a son of King Cuilén, and the last of the descendants of King Æd (d. 878) to hold the kingship. He was killed by Kenneth III, a member of the rival branch of the royal dynasty, at ‘Rathinveramon’ (literally the ‘fort on the mouth of the river Almond’) which is unidentified, but probably near Scone, north of Perth. He is known from late medieval histories as Constantine the Bald.

Dauvit Broun