a mod that adds the English Heptarchies and more.
The four main kingdoms in Anglo-Saxon England were:
East Anglia
Mercia
Northumbria, including sub-kingdoms Bernicia and Deira
Wessex
The other main kingdoms, which were conquered and absorbed by others entirely at some point in their history, before the unification of England, are:
Essex
Kent
Sussex
Other civs which aren't apart of the Heptarchy but had major influence during the time of it
Danelaw
Alba
Gwynedd
The Isles
Dublin