After the American Revolution, Connecticut and most northern states abolished slavery. The port's decline began in the early 19th century during the period of strained American-British relations and resulting trade restrictions, which led to the War of 1812. The port never recovered from the restrictions of the war. The city's men distinguished themselves in the war effort, as Middletown's Commodore Thomas Macdonough led American forces to the victory on Lake Champlain in 1814 which ended British hopes for an invasion of New York. After the war, migration of New England families continued west to New York and, later, to the Midwest around the Great Lakes, where more land was available.