>>2186849
Literally less than a decade before the game start, scottland was fully occupied by england and only made independent by rebellion.
In practice the unification of Britain was peaceful, but if it couldn't have happened peacefully then the overwhelming stabilizing force was towards annexation of scotland by england.

Scotland was a massive pain in the dick for england as long as it remained independent by design. By the mid 1800s it seems extremely unlikely to me that they would continue to exist