1747.
During the years 1747 and 1748, the regiment again served as Marines on board the fleet.
1748.
On the 7th of October 1748, the Treaty of Aix-la-Chapelle was signed, which terminated the war, and the regiment was again stationed in Ireland, where it remained upwards of five years.
1751.
In the royal warrant, dated the 1st of July 1751, for establishing and maintaining uniformity in the clothing, standards, and colours of the army, and regulating the number and rank of regiments, the facings of the Thirty-ninth regiment were directed to be green. The first, or King’s colour, was the Great Union; the second, or regimental colour, was of green silk, with the Union in the upper canton; in the centre of the colour the number of the rank of the regiment, in gold Roman characters, within a wreath of roses and thistles on the same stalk.
At this period the uniform of the regiment was cocked hats bound with white lace; scarlet coats faced and turned up with green, and ornamented with white lace; scarlet waistcoats and breeches; white gaiters, white cravats, and buff belts.
1752.
Colonel John Adlercron was appointed to the colonelcy of the Thirty-ninth regiment on the 14th of March 1752, in succession to Brigadier-General Edward Richbell, removed to the Seventeenth foot.