The Battle of Trois-Rivières was fought on June 8, 1776, during the American Revolutionary War. A British army under Quebec Governor Guy Carleton defeated an attempt by units from the Continental Army under the command of Brigadier General William Thompson to stop a British advance up the Saint Lawrence River valley. The battle occurred as a part of the American colonists' invasion of Quebec, which had begun in September 1775 with the goal of removing the province from British rule. On May 15, Bedel learned that a British force of about 150 British troops of the 8th Regiment of Foot and about 500 Iroquois commanded by Captain George Forster was headed toward The Cedars. The Continental Army, which had invaded Quebec in September 1775, suffered a severe blow in the disastrous attack on Quebec City on New Year's Eve in 1775. Following that loss, Benedict Arnold and the remnants of the army besieged Quebec until May 1776. Bedel left Major Isaac Butterfield in charge of the post and then left for Montreal for reinforcements. Hazen directed Major Henry Sherburne's relief force of 100 men toward The Cedars, but it arrived too late. On May 16, Sherburne's relief force started towards The Cedars. Arnold started to gather a larger force to send a little while later. Forster's British force confronted the smaller American garrison and Butterfield surrendered the garrison without a fight.

He agreed to a cartel with Forster in which that Butterfield received assurances that the Americans would be protected from the Indians accompanying him in exchange for the British to acquire the post. On May 20, Sherburne's relief force landed at Quinze Chiens, located 9 miles from The Cedars. They did not know that Butterfield had already surrendered. They marched into a British ambush about 4 miles from The Cedars. They fought the British for about 40 minutes before they were forced to surrender. The British executed 2 prisoners that night and 5 were later tortured and killed by the Iroquois. Scattered fragments of the American army made their way overland on the northern shore to Berthier, where they crossed over to Sorel. Some did not return until June 11. Sullivan, who counted 2,500 effective troops under his command, at first wanted to make a stand at Sorel, but smallpox, desertions, and word that the British fleet was again under sail to come upriver convinced him it was time to retreat. By June 17, the Continental Army had left the province; but not before it had attempted to burn Montreal, as well as destroying Fort Saint-Jean and any boats of military value capable of navigating Lake Champlain. The captives were treated quite generously by Carleton. Although the conditions of their imprisonment were not always good, he provided them with clothing, and eventually had all but the officers transported to New York and released.