The Aroostook War was really not a war at all. When Maine became a state in 1820, settlers were granted land on both sides of the Aroostook River despite the fact that the British also claimed that area. The U.S. government was not able to work out an agreement and in January 1839, Americans were determined to get rid of the Canadian lumberjacks in the disputed territory. A leader of the Americans was arrested and Maine troops quickly flooded into the area. The state of Maine appealed to the federal government for even more troops and the state was granted a force of 50,000 and $10 million if a war actually broke out. General Winfield Scott was sent to meet with the lieutenant governor of New Brunswick. Scott had an impressive background having served in the War of 1812, participated in enforcement of the tariff of 1828 and the removal of the Cherokee. Finally recognizing the seriousness of the situation, Great Britain agreed to set up a commission to reach a resolution. The result was the Webster-Ashburton Treaty of 1842 which settled the northern border of Maine as seen in the map to the right.
General Winfield ScottSources and further reading on the war and the treaty: