The War of Jenkins' Ear (named for a 1731 incident in which a Spanish commander chopped off the ear of British merchant captain Robert Jenkins and told him to take it to his king, George II) broke out in 1739 between Spain and Great Britain, but was confined to the Caribbean Sea and conflict between Spanish Florida and the neighboring British Province of Georgia. The War of the Austrian Succession, nominally a struggle over the legitimacy of the accession of Maria Theresa to the Austrian throne, began in 1740, but at first did not involve either Britain or Spain militarily. Britain was drawn diplomatically into that conflict in 1742 as an ally of Austria and an opponent of France and Prussia, but open hostilities between them did not take place until 1743 at Dettingen, and war was only formally declared between Britain and France in March 1744. Massachusetts did not declare war until June 2.
The war was also fought on the frontiers between the northern British colonies and New France. Skirmishing and raiding on the northernmost communities of Massachusetts prompted Governor William Shirley to order the construction of a chain of frontier outposts stretching all the way to its border with New York.
On November 28, 1745, the French with their Indian allies raided and destroyed the village of Saratoga, New York, killing and capturing more than one hundred of its inhabitants. All of the British settlements north of Albany were accordingly abandoned. In July 1746 an Iroquois and intercolonial force assembled in northern New York for a retaliatory attack against Canada. British regulars expected to participate never arrived, and the attack was called off. A large (1,000+ man) French and Indian force mustered to raid in the upper Hudson River valley in 1746 instead raided in the Hoosac River valley, including an attack on Fort Massachusetts (at present-day North Adams, Massachusetts), made in revenge for the slaying of an Indian leader in an earlier skirmish. In 1748, Indian allies of the French attacked Schenectady, New York.
The war took a heavy toll, especially in the northern British colonies. The losses of Massachusetts men alone in 1745–46 have been estimated as 8% of that colony's adult male population.
According to the Treaty of Aix-la-Chapelle, Louisbourg was returned to France three years later, in exchange for the city of Madras in India, captured by the French from the British. This decision outraged New Englanders, particularly Massachusetts colonists who had contributed the most (in terms of funding and personnel) to the expedition. The British government eventually acknowledged their effort with a payment of £180,000 after the war, which the province used to retire its devalued paper currency.
The peace treaty, which restored all colonial borders to their pre-war status, did little to end the lingering enmity between France, Britain, and their respective colonies, nor did it resolve any territorial disputes. Tensions remained in both North America and Europe, and were reignited with the 1754 outbreak of the French and Indian War in North America, which spread to Europe two years later as the Seven Years' War. In Acadia and Nova Scotia, war continued in Father Le Loutre's War.