During the American Revolutionary War, he led militia troops at the battles of Trenton, Princeton, Brandywine and Germantown. In April 1777, he was promoted to brigadier-general of the Pennsylvania militia. In 1777, with the troops under his command in the counties of Philadelphia, Chester, and Delaware, he obtained important information for George Washington, and prevented supplies from reaching the enemy. On 11 December, while the army under Washington was on its way to Valley Forge, after part of it had crossed the Schuylkill River at Matson's Ford, it was found that the enemy under Cornwallis were in force on the other side. "They were met," writes Washington, "by General Potter, with part of the Pennsylvania Militia, who behaved with great bravery, and gave them every possible opposition until he was obliged to retreat from their superior numbers. " On this same day a group of Pennsylvania Militia under the command of General Potter defended the home of Thomas Wynne of Blockley from a band of British marauders. The graves of three British soldiers killed are on the Wynnestay property. After this day of service, Potter took a leave of absence to care for his sick wife. Accompanying General Potter through the Revolutionary War was his servant Hero Wade.