From The Plains of Abraham by Brian Connell:
But direct action (destroying Oswego) would have meant re-opening hostilities and that far the French were not prepared to go. Instead, La Jonquiere turned his attention to a project of more immediate strategic value. The commissioners in Paris had another bone of contention in the north--the exact extent and ownership of Acadia, the peninsula now known as Nova Scotia. The French had never reconciled themselves to the loss of this part of their possessions at the end of Marlborough's wars in 1713. The British were requiring the inhabitants, still entirely French in blood and language, to take a simple oath of allegiance to George II. ....Threatened with excommunication by their own priests...and under fear of massacre by suborned Indians, more than two thousand Acadians were persuaded to move to the mainland rather than take the new oath of allegiance.