The Undeclared War Between Britain and America, Part II: 1837-1842
Henry I. Kurtz describes how many of the outstanding problems between Britain and the United States were settled by the Webster-Ashburton Treaty of 1842.
It was while in New York in 1839 on final round of stumping the country in the cause of peace that General Winfield Scott learned of the flare-up of the Maine boundary dispute. The unsettled north-east boundary of the United States had been an open sore since 1783, when the Treaty of Paris was signed.
At that time, John Adams and the American commissioners, along with their British counterparts, had drawn the boundary line on several copies of the 1775 edition of Mitchell’s Map of North America.
Complications later arose because of the vague wording of the provisions applying to the boundary settlement, cartographical errors, and the fact that soon after the negotiations the maps used by the commissioners disappeared.