The Seven Years' War, 1756-1763
Britain was at war with Spain, and with France, between 1739 and 1748. The results of that contest was inconclusive, and there was no fighting in Newfoundland - no doubt because the French had lost their base at Placentia. However, Anglo-French relations remained tense, particularly in North America, and a long-expected war broke out in May, 1756.
Once they had established naval superiority at sea, the British made a series of impressive gains at the expense of France and, later on, of Spain. Slaving stations in West Africa, sugar islands in the Caribbean, and large parts of India all came under British control.
In 1758 the British mounted an attack on New France by land and by sea. The French fortress at Louisbourg on Cape Breton Island fell in 1758. And on 13 September 1759, General James Wolfe defeated the French forces at Québec. By the autumn of 1760, French America had become British.
Towards the very end of the war, in 1762, French forces attacked St. John's. If successful, the expedition would have strengthened France's hand at the negotiating table. Though they took St. John's and raided nearby settlements, the French forces were eventually defeated by British troops under Colonel William Amherst.
The war ended with the Treaty of Paris, signed in 1763. It contained important clauses relating to Newfoundland, including the cession to France of the islands of St. Pierre and Miquelon.