system
Given the following post, respond as if you're commenting on Reddit:
human
[ELI5] The origins of England: Who were the Anglos, the Saxons, the Normans, etc?
gpt
The place we call England has been invaded and occupied a bunch of times.

As far as we can tell, the first inhabitants of the area were people called Britons. Britons were a Celtic people who spoke their own version of the language. The Welsh and Cornish languages are closely related to this.

The Romans invaded South East England in 43 AD, and a hybrid Roman/British culture sprang up. Romans ruled the area for about 500 years.

Then you have what is called the Anglo-Saxon settlement period. Basically a bunch of tribes from around modern day Germany invaded/settled Britain, forcing the native Britons west into Wales, Cornwall & the North. These newcomers were fleeing invasion themselves, but were kind of massive dicks to the Britons. They spoke a bunch of different languages, but mostly started what we call Old English.

There were now a bunch of different kingdoms/states in Britain (like Wessex, Northumbria, Mercia etc), and they fought each other on and off for ages. Vikings also invaded and tried to settle, especially areas like York and Norwich (called the Danelaw).

Eventually the Kingdom of Wessex won, uniting the Anglo-Saxon kingdoms & driving out the vikings, and the Kingdom of England was established about 1000AD.

It wasn't long before they were invaded again though. The Normans (from northern France) invaded and conquered England in 1066. The Normans spoke a form of French.

From then England was pretty much a sovereign, solid concept. The remaining areas of Wales, Scotland and Ireland were conquered over time, to vary degrees of success. Note: this is a very rough overview, and I've glossed over a lot of stuff.