King George's War named for King George II of Britain, grew out of the struggle in Europe known as the War of the Austrian Succession. The fighting in North America began when the French tried unsuccessfully to regain Nova Scotia. The greatest battle of the war occurred in 1745, when New England colonial troops under William Pepperrell captured the French fortress of Louisbourg on Cape Breton Island. The Treaty of Aix-la-Chapelle, which ended the war, gave back to Britain and France the territory each side had lost in the war.