The formation of the regiment was prompted by the expansion of the army as a result of the commencement of the Seven Years' War. On 25 August 1756 it was ordered that a number of existing regiments should raise a second battalion; among those chosen was the 31st Regiment of Foot. The 2nd Battalion of the 31st Regiment of Foot was formed on 10 December 1756 and renumbered as the 70th (Glasgow Lowland) Regiment of Foot on 21 April 1758. The regiment was sent to Ireland in 1763 and on to the West Indies in 1764 where it suffered serious losses due to illness before returning home in 1774. It embarked for North America in 1775 for service in the American Revolutionary War. It was involved in the Battle of Sullivan's Island in June 1776 and the attack on Fort Lafayette in June 1779. The regiment acquired a county designation as the 70th (Surrey) Regiment of Foot in 1782 before returning home in 1784.