stripped of troops to support usurpers' claims to the Roman empire, and after 410 the Roman armies never returned. Sources for events after this date are extremely scarce, but a tradition, reported as early as the mid-6th century by a British priest named Gildas, records that the British sent for help against the barbarians to Aetius, a Roman consul, probably in the late 440s. No help came. Subsequently, a British leader named Vortigern is supposed to have invited continental mercenaries to help fight the Picts who were attacking from the north. The leaders, whose names are recorded as Hengest and Horsa, rebelled, and a long period of warfare ensued. The invaders—Angles, Saxons, Jutes, and Frisians—gained control of parts of England, but lost a major battle at Mons Badonicus (the location of which is not known). Some authors have speculated that Ælle may have led the Saxon forces at this battle, while others reject the idea out of hand. The British thus gained a respite, and peace lasted at least until the time Gildas was writing: that is, for perhaps forty or fifty years, from around the end of the 5th century until midway through the sixth. Shortly after Gildas's time, the Anglo-Saxon advance was resumed, and by the late 6th century nearly all of southern England was under the control of the continental invaders. Early sources There are two early sources that mention Ælle by name. The earliest is The Ecclesiastical History of the English People, a history of the English church written in 731 by Bede, a Northumbrian monk. Bede mentions Ælle as one of the Anglo-Saxon kings who exercised what he calls "imperium" over "all the provinces south of the river Humber"; "imperium" is usually translated as "overlordship". Bede gives a list of seven kings who held "imperium", and Ælle is the first of them. The other information Bede gives is that Ælle was not a Christian—Bede mentions a later king as "the first to enter the kingdom of heaven". The second source is the Anglo-Saxon Chronicle, a collection of annals assembled in the Kingdom of Wessex in c. 890, during the reign of Alfred the Great. The Chronicle has three entries for Ælle, from 477 to 491, as follows: 477: Ælle and his 3 sons, Cymen and Wlencing and Cissa, came to the land of Britain with 3 ships at the place which is named Cymen's shore,