Following the British Army's successful occupation of New York City in 1776, the second year of the American Revolutionary War, the areas surrounding the city that were between the American and British lines became a no man's land. These areas, which included Westchester County, New York and Greenwich, Connecticut, were frequently the site of raiding actions between the combatants. At the end of 1779 this no man's land included Tarrytown and White Plains. The American lines were not far north of this area, extending into Mount Pleasant. An outpost at Four Corners (in the present-day Thornwood section of Mount Pleasant) occupied particularly advantageous ground, and its occupation was more than once disputed. The outpost was on the property of Joseph Young, a local landowner; his house and barns were occupied by Continental Army troops beginning in August 1776. In December 1778 a British raid captured the small garrison posted there. They burned a barn but did not occupy the post, and it was promptly reoccupied by Continental Army troops in early 1779.