In June 1777, George Washington and his army were encamped along the Middle Brook in the Watchung Mountains when Congress adopted the Stars and Stripes as the official flag of the United States of America, giving rise to Bridgewater's claim as the place where the flag first flew. In December 1778, Washington and his army returned and established a winter encampment on the other side of the mountain. This Second Middlebrook Encampment established cantonments near Bound Brook, Finderne, Martinsville and Pluckemin.