Well in Britain and Brittany a descendent of pre-Roman language still persists to this day, Welsh and Breton. English is certainly more Germanic than it is Romance, but it's inarguably a bit of a hybrid with periodic injections of French throughout the medieval. And Britain was a former province, and the marks of Latin on the language do persist despite the modern language being mostly derived from a Germanic source.

The vast majority of the Romano-British would have spoken common Brittonic, with some speaking bits of Latin, and other languages from around the empire. By around the the 6th century AD the language began to diverge into the ancestors of the modern Brittonic languages, Cornish, Welsh, and Cumbric. Cumbric was fairly quickly replaced by Old English when the Saxons turnt up waving their fancy swords around and being all Germanic everywhere. What is now England came to speak Old English by the 8th century, with the native language becoming increasingly obscured apart from in the fringes of the island. Wales and Cornwall kept ahold of their language until the modern era. Cornish went completely extinct in the 19th century before being revived. It's still very rare.

Migrants from Britain to France brought the Brittonic roots that became Breton, which still survives.