This study presents some of the most important phonological and grammatical phenomena which show the evolution of Late Latin in the Roman province of Britannia. The investigation is based on a corpus of inscriptions on stone (established by Collingwood and Wright). The Vulgar Latin of Britannia seems not very different from that of other provinces, but the progression of certain changes is slower. The author insists on the different origins of soldiers and colonists who took part in the romanization of the island.