Appearence and tactics of early 5th century Saxons.

[Felix]

Those large numbers exist only in theory. because even though the later English kingdoms all produced stories of their ancestors landing at beach A, defeating some Brits and moving inland to point B, no evidence exists that any of these kingdoms really existed before the mid-6th century. The first being Kent and Wessex, both going back on the same legends (Hengist) but neither claiming him as founder. Kent may have started out as a foedus turning independent and may show parallels with the origins of Francia and Bavaria, where essentially soldiers in Roman service found at some point that their generals were in fact left alone, free to rule as leading class. Wessex even starts with 4 British-named kings.

This idea converges with the Romano-British sources which are normally cited in the study of King Arthur - Gildas and Nennius. They assert the English initially came as a few mercenaries, were settled by Romano-British rulers, and only gradually increased in strength. Their rise to power happens partly due to their military power, and partly due to the weakness and instability of the rulers who employ them. These sources do not describe a massive onslaught of invaders who wipe out every living soul in the countryside.