At the time of the Revolution, Philadelphia was the country’s biggest city, its business center, and its unofficial capital. As such, it was chosen as the meeting place of the Continental Congress, which helped unite the thirteen colonies and drew up the Declaration of Independence. Once the war began, many Philadelphia merchants pooled their savings and invested them in building privately-owned iron mills and foundries, hidden away in wooded valleys near the city, where enterprising colonial “industrialists” made cannon and balls for General Washington and his troops. Philadelphia and the surrounding towns also supplied volunteers for Washington’s army. No more colorful and dashing unit responded to the Revolutionary call to arms than the First Troop, Philadelphia City Cavalry, known popularly as the Philadelphia Light Horse, The Troop served as General Washington’s escort when he left Philadelphia to take command in June, 1775 of the Continental Army assembled at Cambridge outside of Boston. The Light Horse Troop rode with a handsome blue-tasseled flag. Against a yellow background it showed a horse, a Continental masquerading as an American Indian, an angel, and the legend, FOR THESE WE STRIVE. In the canton there were seven stripes of silver and six of blue symbolizing the thirteen newly united colonies. These stripes were probably added after 1777, and the canton Washington saw on his way to Cambridge in 1775 was none other than the British Union Jack. The Light Horse later carried its flag in the battles of Trenton, Princeton, Brandywine and Germantown. When the British and Hessian army finally surrendered at Yorktown, Virginia in the fall of 1781 - in the last major battle of the Revolution - it was the celebrated Light Horse Troop that paraded the captured flags through the streets of Philadelphia for official presentation to the Continental Congress.