Serving in the British Army, he rose to Colonel of the 1st Foot Guards 21 August 1795, and Major General 18 June 1798. In 1801 he served under Abercromby and Hely-Hutchinson in the Egyptian Campaign commanding the Guards Brigade, seeing action at Aboukir, and Alexandria (Canope). He was made Lieutenant General on 30 October 1805. In August 1807 he commanded the 3rd Division in the Copenhagen Campaign under Lord Cathcart. Ludlow was promoted General in June 1814.