Over 5 hours of research every day for almost a week for a less than 2-minute long video, list of most relevant sources are listed down below. I plan on making a complete history of the British Isles video soon. Already working on part 2 tho! :)

https://en.wikipedia.org/wiki/Bronze_...
https://en.wikipedia.org/wiki/Ewart_P...
https://www.abroadintheyard.com/mappi...
https://en.wikipedia.org/wiki/Britton...
https://en.wikipedia.org/wiki/Urnfiel...
https://en.wikipedia.org/wiki/Neolith...
https://www.bgs.ac.uk/discoveringGeol...
https://en.wikipedia.org/wiki/Happisb...
https://en.wikipedia.org/wiki/Homo_he...
http://www.northern-england-geology.c...
https://en.wikipedia.org/wiki/Shetlan...
http://cw.routledge.com/textbooks/res...
https://en.wikipedia.org/wiki/Beaker_...
https://en.wikipedia.org/wiki/Timelin...
https://en.wikipedia.org/wiki/Prehist...)
https://en.wikipedia.org/wiki/Hallsta...
https://en.wikipedia.org/wiki/Neander...
https://en.wikipedia.org/wiki/Atlanti...
https://en.wikipedia.org/wiki/Wessex_...
https://en.wikipedia.org/wiki/Prehist...
https://en.wikipedia.org/wiki/Ancient...