In February 1702, Meredyth was appointed Colonel of the 37th Regiment of Foot in the expansion of the Army prior to the War of the Spanish Succession. The regiment was part of the force led by the Duke of Marlborough and Meredyth was promoted Brigadier-General after Blenheim in August 1704. Now in command of a Brigade, he participated in the campaigns of 1705 and 1706, including the Moselle expedition and the forcing of the French lines at Eliksem and Neer-Hespen.