George Cadogan , 3rd Earl Cadogan Admiral George Cadogan , 3rd Earl Cadogan , CB , KMT ( 5 May 1783 - 15 Sep 1864 ) was a prominent British Royal Navy officer and politician of the mid - nineteenth century who first gained notoriety for his service in the Adriatic campaign of the Napoleonic Wars in command of . Cadogan later served as aide - de - camp to successive British monarchs and received promotion to full admiral . The son of Charles Cadogan , 3rd Baron Cadogan and his second wife Mary Churchill , Cadogan inherited his father ' s titles from his half brother Charles in 1832 and became the third Earl Cadogan . He was also created 1st Baron Oakley of Caversham on 10 September 1831 . Later in life , Cadogan was elected to become a Fellow of the Society of Antiquaries of London and died in 1864 . Life . George Cadogan was born in 1783 at St James ' s Square in London , the eighth son of Charles Cadogan , 3rd Baron Cadogan and the second son of Mary Churchill , the Baron ' s second wife . George would follow his brother Thomas , 29 years his senior , into the Royal Navy , although Thomas had drowned in an accident in 1782 . Joining the Navy aged 13 in 1796 , Cadogan served in the French Revolutionary Wars . By 1807 , George was a Post Captain and in 1811 he was given command of the newly commissioned HMS " Havannah " , a 36 - gun fifth rate frigate . In 1812 " Havannah " was ordered to the Adriatic , to reinforce the British squadron there that had already defeated the French forces in the area at several battles in 1811 . " Havannah " was based at the island of Lissa , but in 1813 Cadogan was ordered to operate against the Northern Italian coastline in conjunction with the approaching forces of the Austrian Empire during the War of the Sixth Coalition . Cadogan was highly successful in this endeavour , destroying or capturing numerous French and Italian ships off Vasto and other ports on the French - held coastline . In October 1813 , Cadogan was attached to the force under Thomas Fremantle that forced the surrender of Trieste and later in the year " Havannah " successfully captured Zara from the French garrison in a daring coastal raid . In 1815 , Cadogan returned to Britain and was made Companion of the Order of the Bath . The untimely deaths of six of Cadogan ' s seven brothers brought him the title of Earl Cadogan ( which his father had been awarded in 1800 ) on the death of his eldest brother Charles Cadogan , 2nd Earl Cadogan in 1832 . Cadogan took his seat in the House of Lords , but remained a prominent naval officer , continuing to rise in the service and serving as aide - de - camp to King William IV between 1830 and 1837 and Queen Victoria between 1837 and 1841 . By 1851 , Cadogan was a vice - admiral and in 1852 he became a fellow of the Society of Antiquaries of London . Cadogan died a full admiral in 1864 in his London home in Piccadilly . Cadogan was married to Honoria Louisa Balke and the couple had five children , the eldest surviving son of whom , Henry , became on his death 4th Earl Cadogan and the fifth General Sir George Cadogan of the British Army . As a naval captain in 1809 he fought a duel with Lord Paget , who had seduced Cadogan ' s sister - in - law . His youngest son Frederick William Cadogan sat as Member of Parliament for Cricklade .