The British defeated the Americans and forced them into a retreat that "nearly developed into a stampede." Mathews's regiment was one of the last to leave the field of battle, causing some to credit him for saving the American army from rout. Following its victory, the British army set up camp in Germantown. On October 4, General Washington launched an attack on the British camp, initiating the Battle of Germantown. Mathews led a charge early in the day that resulted in the capture up to 100 British soldiers; however, as the day progressed Mathews penetrated so deeply into British lines that he became isolated from Washington's army and was engulfed by opposing troops. This resulted in the capture or death of his entire regiment, with Mathews claiming to have "bled from five wounds" during the ordeal. The given reasons for his capture vary; some claim he did not receive Washington's orders to retreat, while others claim his regiment became lost in the fog and smoke of battle. Nationally, he received acclaim and his reputation grew as a result of his daring. He spent much of the remaining revolution as a prisoner of war, first held at Philadelphia, and later on a prison ship anchored in New York harbor. The severity of Mathews's injuries caused a British surgeon to deem him "incurable." By 1779, however, Mathews recovered was granted a limited parole and permitted to live in New York City. He wrote to Governor Thomas Jefferson and to the Continental Congress urging a prisoner exchange. Jefferson wrote to Mathews to explain his decision to leave him in New York City as a parolee and instead exchange for others still suffering in much worse conditions on the prison ships. Mathews turned his attention toward the improvement of living conditions for fellow prisoners of war, securing money and provisions for this aim from Congress and the State of Virginia. He was formally exchanged on December 5, 1781, at which point he was given command of the 3rd Virginia Regiment and went with Major General Nathaniel Greene into the southern theater, though he saw no further action in the war. Mathews was brevetted brigadier general at the end of the war; on September 30, 1783, Congress conferred a "general brevet" on the officers Continental Army, advancing all below the rank of major general by one rank. Mathews was an Original Member of the Society