Right, so here we are right in the middle of all the drama and bloodshed that has been called the Anglo Saxon invasion. We have famous names such as Hengest and Aelle showing up.
And most everyone who is interested in this story is probably already familiar with the story of how (following the issue with Hengest and Vortigern) you had warlords like Aelle and Cerdic showing up and parcelling out the land. The north was taken by the Angles, the South was mostly taken by the Saxons, and then the Jutes took a little bit in the south as well.
But the thing about this story, the thing that makes telling it really difficult, is that there’s a not insignificant chance that it’s utter bollocks.
So what do we know? Well, we know that Gildas, Bede, and others have told stories about invasion. We know that at one point most of the Britons in the area were speaking Latin and some sort of Brythonic language, and it didn’t take too long before they were speaking Old English (which is a Germanic language… which comes from the same group of peoples that we’re told invaded). We know that Christianity, which was present in the lands that would become England, largely died out and paganism (which still held on in the homelands of the Anglo Saxons) became resurgent.