Washington appointed Arnold military commander of the city in 1778

Another fact is that Washington appointed Arnold military commander of the city in 1778. Arnold was severely wounded in his left leg during the battle of Bemis Heights on October 7, 1777, the same leg that had been damaged during his assault on Quebec in 1775. It required many operations and months of recovery in an Albany, New York hospital for him to be able to return to duty, and he would always walk with a limp, his left leg two inches shorter than his right.

In June 1778, the British withdrew from Philadelphia, and Washington appointed Arnold military commander of the city. Even before the Americans reclaimed control of Philadelphia, Arnold began making financial plans to benefit from the change in power. He engaged in a number of business transactions in order to profit from war-related supply flows and benefit from his authority's protection.

Such schemes were not uncommon among American officers, but Arnold's attempts were occasionally thwarted by powerful local politicians like Joseph Reed, who eventually gathered enough evidence to accuse him publicly. In a letter to Washington in May 1779, Arnold urged a court martial to clear his name, saying, "Having become a cripple in the service of my country, I little expected to meet ungrateful returns."