Lumberjacks from New Brunswick and Canada entered the Aroostook region to cut timber during the winter of 1838-1839, and in February they seized the American land agent who had been dispatched to expel them. The "war" was now under way.
Maine and New Brunswick called out their militiamen, and the United States Congress, at the instigation of Maine, authorized a force of 50,000 men and appropriated $10 million to meet the emergency. Maine actually sent 10,000 troops to the disputed area. President Martin Van Buren dispatched General Winfield Scott to the "war" zone, and Scott arranged an agreement in March of 1839 between officials of Maine and New Brunswick that averted actual fighting. Britain agreed to refer the dispute to a boundary commission, and the matter settled in 1842 by the Webster-Ashburton Treaty. After years of bickering over all the variances, the matter was settled with a simple straight line drawn with a ruler between two points on the map.
The compromise reached by Daniel Webster and 1st Baron Ashburton awarded 7,015 square miles to the United States and 5,012 to Great Britain. Retention by the British of the northern area assured them of year-round overland military communications with Montreal. Webster used a map, said to have been marked with a red line by Benjamin Franklin at Paris in 1782, to persuade Maine and Massachusetts to accept the agreement. Britain agreed to pay these states $150,000 each, and they were to be reimbursed by the United States for expenses incurred defending the area against encroachment.
The war, while lacking actual combat, did not lack for casualties. Hiram Smith, a Mainer, died of unknown causes while in service to his state.