He was born in County Longford, Ireland, emigrated to British America, married in 1767 in Philadelphia, Pennsylvania, and joined the carpenter's guild in 1772.

Secretary of War Henry Knox named him to go on a peace mission in 1791 to the Native American tribes near Lake Erie.

[3] Proctor asked the state Council of Safety to appoint him captain on October 27 and his request was immediately granted.

[4] While other state troops were sent to the Flying Camp (reserve), the artillery company was retained near Philadelphia to defend Fort Island.

[7] In the Battle of the Assunpink Creek on January 2, 1777, Forrest had six cannons supporting a 1,000-man delaying force under Edward Hand.

Proctor capably performed this duty, though some Continental officers were annoyed that a man with a state commission was elevated above them.

A company from the regiment was roughly handled at the Battle of Bound Brook on April 13, losing two cannons, two officers and about 20 men captured.

[3] Washington ordered Proctor's regiment to Trenton, New Jersey, to join Francis Nash's brigade where it arrived about July 24.

After getting news of the British landing in Chesapeake Bay, Nash's troops and Proctor's gunners were instructed to move to Chester, Pennsylvania, on August 22.

[4] During the Battle of Brandywine on September 11, 1777, Proctor's Pennsylvania Artillery manned a 4-gun lunette on a knoll that overlooked Chadds Ford.

Firing canister shot, Proctor's guns caused considerable casualties before the British successfully stormed the lunette.

[15] During the Battle of Germantown on October 4, 1777, the American first wave encountered 100–120 men of the British 40th Regiment of Foot shut up in the Benjamin Chew House and flowed around the obstacle.

For two hours, the guns blasted the masonry with round shot or fired canister at the second story, but all American infantry attacks were repulsed with heavy losses.

[16] On February 27, 1778, Washington wrote from Valley Forge that Proctor's Regiment suffered "considerable" casualties in the 1777 campaign and serious desertion since.

[4] At the Battle of Monmouth on 28 June 1778, Proctor led 12 guns in William Alexander, Lord Stirling's wing which was in Washington's main body.

Under the direction of Knox, the 12 guns were massed in a large battery on the forward slope of Perrine's Ridge about 1:00–1:30 pm.

At this time Proctor demanded new uniforms which were supposed to be black for the artillery, but he insisted on letting his officers wear blue coats.

[21] The expedition ruined the Iroquois Nation by wrecking their towns and burning their crops, but it did not stop the warriors from attacking American settlements.

The cattle raid was successful but the Americans were unable to storm a blockhouse manned by Loyalists despite a bombardment by four cannons.

Proctor's role is known because British Major John André penned a satirical poem about the battle called the Cow Chace that mentioned the American artilleryman.

Infuriated over the Pennsylvania Council's promotion of officers without his approval, Proctor tendered his resignation on April 9, 1781.

I cannot in justice to you permit you to leave the army without expressing my approbation of your conduct upon every occasion since you joined me in 1776, and wish you success in the line of life which you have now embraced."

On March 10, 1791, Knox, now Secretary of War appointed him to go on a peace mission to the Wabash and Miami tribes near Lake Erie.

Governor Thomas Mifflin appointed Proctor a major of artillery on May 17, 1792, and brigadier general of militia on April 12, 1793.