The colonial region renamed Nova Scotia after Britain gained control from France was Acadia.
Acadia was a French colony in northeastern North America that included present-day mainland Nova Scotia, New Brunswick, parts of Prince Edward Island, the Gaspé Peninsula, and areas of present-day Maine. Its boundaries were never perfectly fixed, making the term broader and more contested than the later province of Nova Scotia.
Britain captured Port Royal, Acadia’s principal settlement, in 1710 during Queen Anne’s War. The Treaty of Utrecht in 1713 formally transferred mainland Acadia to Britain, which used the name Nova Scotia for the colony. The name had actually been proposed much earlier, in 1621, but British rule made it the established colonial designation.
The transfer did not settle every territorial question. France retained Île Royale, now Cape Breton Island, and Île Saint-Jean, now Prince Edward Island, while areas around New Brunswick and Maine remained disputed. Acadians also continued living under British rule, and tensions over allegiance later contributed to the Acadian deportation.