William Cadogan , 1st Earl Cadogan William Cadogan , 1st Earl Cadogan KT PC ( 1675 – 17 July 1726 ) was a noted military officer in the army of John Churchill , 1st Duke of Marlborough during the War of the Spanish Succession . He commanded the 1st Foot Guards for some time . Early life . The eldest son of barrister Henry Cadogan , he was educated at Westminster School and Trinity College , Dublin , and joined the army in 1690 . He served in Ireland at the sieges of Cork and Kinsale where he first served with Marlborough , then an Earl , and by 1701 was a Major of the Inniskilling Dragoons . War of the Spanish Succession . In 1701 , Cadogan was appointed quartermaster general to Marlborough on the latter ' s appointment to command the English troops in the Low Countries . During the campaign of 1704 , he was one of the few entrusted with the truth of Marlborough ' s march from the Spanish Netherlands to the Danube and played a major role in the organisation of the march . He fought at the battles of the Schellenberg and Blenheim . Shortly after he was promoted to Brigadier General and became Marlborough ' s Chief of Staff . He commanded the army ' s scouting part which located the French army on the morning of Ramillies , and acted as a senior messenger for Marlborough during the battle , recalling Orkney ' s British infantry from their diversionary attack on the French right flank to assault the French centre around Ramillies itself . At Oudenarde he commanded the allied advance guard , which established crossings over the River Scheldt . In 1706 he was promoted to major - general and commanded the forces which broke through the French left towards the end of the battle . In 1709 he was promoted to lieutenant - general . He fought at Malplaquet , and was wounded in the neck at the siege of Mons , but quickly recovered . At the end of 1709 Cadogan was appointed as a Lieutenant of the Tower of London . During the breaking of the lines of Ne Plus Ultra , he again commanded the allied advance guard , and established a bridgehead across the lines prior to Marlborough ' s arrival with the main army . After Marlborough ' s dismissal from his posts at the end of 1711 Cadogan remained with the army , but refused to return with it when Britain withdrew from war in 1712 , going into voluntary exile with the Duke . In doing so he lost his rank , positions and emoluments under the crown . George I on his accession , in 1714 , reinstated Cadogan , and , amongst other appointments , made him Lieutenant of the Ordnance , under Thomas Erle . Later life . During Marlborough ' s voluntary exile during the last years of Queen Anne ' s reign , Cadogan accompanied him , and often acted as a go - between to maintain Marlborough ' s links with Britain . When the Hanoverian King George I succeeded in 1714 , Cadogan received military favours from the Crown , and in 1715 he replaced the Duke of Argyll in command of the army putting down a Jacobite rising . On 21 June 1716 , he was made Baron Cadogan of Reading , having recently purchased Caversham Park , Oxfordshire ( now Berkshire ) near that town . He was also made a Knight of the Thistle and , the following year , a member of the Privy Council . ( He was a Whig MP for Woodstock from 1705 to 1716 . ) On 8 May 1718 George I made him 1st Baron Cadogan , of Oakley , co . Buckingham , Viscount Caversham , of Caversham , co . Oxford and Earl Cadogan . In later years he also served as Master of the Robes ( 1714 – 1726 ) , Governor of the Isle of Wight ( 1715 – 1726 ) and Master - General of the Ordnance ( 1722 – 1725 ) . However , the Opposition ' s staunch hostility towards him meant that he had lost any political influence several years before his death on 17 July 1726 . He married Margaret Cecilia Munter in April 1704 at The Hague . They had two daughters : Sarah ( born 18 September 1705 ) , who married Charles Lennox , 2nd Duke of Richmond , and Margaret ( born 21 February 1707 ) , who married the Hon . Charles John Bentinck , fourth son of William Bentinck , 1st Earl of Portland .