Following the Battle of Princeton, the 17th Regiment once again went into winter quarters, this time at Brunswick. The regiment marched with the rest of the army to New York in the spring of 1777 and boarded transports for Head of Elk. The 17th took part in the 1777 Philadelphia campaign as part of the 4th Brigade, which included the 35th and 64th Regiments of Foot.While serving in the reserve for the opening movements of the campaign, the 17th Regiment was actively engaged at the Battle of Brandywine, where its light company, serving with the 1st Battalion of Light Infantry, was immortalized by the account of its actions contained in Feinstone 111, one of the few surviving accounts of light infantry actions during the war.
When Earl Cornwallis took Philadelphia in late September 1777, the Grenadier Company of the 17th Regiment was with them. Under the command of Captain Brereton, the 17th Grenadiers not only took the rebel Delaware frigate, but also distinguished themselves during the fighting on Providence Island. On October 4th, when Washington’s army attacked the British positions at Germantown, the regiment again played a vital role in coming to the relief of the 40th Regiment of Foot, which was ensconced in the Chew House. Major André provided a brief account of the 17th’s conduct in his journal entry for the battle: “The 4th Brigade received Orders by inclining to their right to enter German Town and drive the Enemy from it. From some misunderstanding, or from receiving some fire, they did not immediately go into the village, but halted on the skirts of it, and kept up a very heavy fire against a distant Column they had some intimation of in front. The 17th and 44th Regiments were therefore ordered to wheel to the right and drive out the Rebels. This was executed, the 44th crossing the village and moving up the skirts on the opposite side, and the 17th moving up the street. General Grey headed the 44th Regiment. Lord Cornwallis came up as the Rebels had retired, and took the command of the left wing, with which he pursued as far as Whitemarsh Church, leaving a Corps at Chestnut Hill.”
The 17th Regiment remained in garrison at Philadelphia with the rest of the army through the transition of power from Howe to Clinton. When the city was evacuated in June 1778, the regiment marched as part of the 3rd Brigade and fought beside the Guards at the Battle of Freehold (Monmouth Courthouse) June 28, 1778. After successfully defeating the rebel assault, the 17th withdrew with the army to New York and remained on duty there until August.