Alexander Cavalié Mercer (1783—1868) is quite well-known due to his command of a troop of horse artillery at the Battle of Waterloo, and his subsequent memoir of the campaign, Journal of the Waterloo Campaign (1870). The rest of the family has not received so much recognition.
Alexander Cavalié’s father, Alexander Mercer (ca. 1739—1816) had a distinguished career in the Royal Engineers, rising ultimately to become a General and Colonel Commandant. Joining the army in 1759 he saw service in the Seven Years’ War in France and the Mediterranean, in the American War of Independence, in the West Indies, at Guernsey, and in England. Alexander Mercer and his wife, Thedosia Dickson, had five children who survived to adulthood, of whom all four sons served in the armed forces, and the daughter married a naval Captain.
Alexander Cavalié was the eldest. He is said to have been the second son, but the first must have died young and I have no record of him. After attending the Royal Military Academy at Woolwich, he was commissioned into the Royal Artillery in 1799. He served in Ireland for the first few years of his career and was part of the unfortunate attempt to seize Buenos Aires in 1807. He then languished in England until called upon to lead his company of Royal Horse Artillery to the Continent in 1815. Although his account of the Waterloo campaign has assured his fame, the fact that he had disobeyed Wellington’s orders during the battle did nothing to enhance his career. Shortly after his return to England in 1816 he was reduced to half pay. He had married Frances (Fanny) Rice (1793—1817), daughter of an English clergyman, in 1813. They had lost their first child, but after the war was over, while his company was still in France, she joined him and her presence gives a light touch to the latter portions of the narrative (he refers to her only as F.). In 1817, they had another son, Cavalié Alexander Mercer (1817—1882), but Fanny died, and was buried three days after the child was born.
Eventually, Alexander Cavalié was reinstated in the Army and posted to Canada in 1823. After a spell in England, he was gain sent to Canada, serving there from 1837 to 1842 as a lieutenant-colonel in command of the artillery at Nova Scotia. While there he made a number sketches and watercolours, some of which are now held by the National Gallery of Canada.
After his service in Canada, he returned to England, gradually rising through the ranks to become a general and colonel-commandant of the 9th brigade of the Royal Artillery.
The second of Alexander Mercer’s children was the daughter, named Theodosia after her mother. Theodosia Mercer (1784—1881) married Hector Frederick McNeill, a Captain in the Royal Navy, in 1804. They do not appear to have had any children and after she was widowed she lived for a time in Scotland with her aunt, before moving to Devon to live near her brother.
Next was Augustus Cavalie Mercer (1785—1825). He joined the 9th Regiment of Foot, becoming Lieutenant in 1804 and Captain in 1805. In 1808, the 9th Foot deployed to Portugal as part of the British forces in the Peninsular War, and it was on board ship at Lisbon that in 1809 he married Mary Anne March, presumably of the March trading family in Lisbon. In 1814, back in England, Augustus became a Captain of one of the new Garrison Companies, although he was placed on half pay in November 1816. He died in 1825 in the military hospital at Chatham. He and Mary Anne do not appear to have had any children.
The third brother was Cavalie Shorthose Mercer (1789—1819). He was the only one to follow his father into the Royal Engineers, becoming 2nd Lieutenant in 1804 and 1st Lieutenant in 1805, and posted to Gibraltar in late 1805. He was one of the first engineers to go to Portugal at the beginning of the Peninsular War in August 1808. In 1810 he was promoted to 2nd Captain and made Captain in October 1813. At some point he met and married a young Cornish girl, Elizabeth Birt Alice Holmes (1800—1863) and they had two daughters, Theodosia Alice Sterling baptized on the first of January 1818 in Cornwall, and Henrietta Fyers Mercer baptized 31 December 1818 in Bermuda.
The posting to Bermuda was unfortunate. In 1819 there was a severe outbreak of yellow fever which ravaged the company and killed Cavalie Shorthose. His will closes, “My dear father and mother and brother in law I have ever regarded you with the tenderest esteem never neglect my children”. The History of the Corps of Royal Sappers and Miners, by Thomas Connolly says, “An epidemic fever of a severe character raged at Bermuda during the months of August and September, and out of a company of fifty-two total, no less than one sergeant, twenty rank and file, three women, and one child, fell victims to its virulence. Captain Cavalie S. Mercer who commanded the company, was also numbered with the dead”.
His young widow returned to England with her two small daughters. In 1822, she married John Reed of the 62nd Regiment of Foot. In 1830 the regiment was posted to India and there her elder daughter Theodosia died at Bangalore in 1832, aged 15. John Reed himself, by then a Lieutenant-Colonel died in 1835. For her third husband, she married a Cornish doctor, John Francis Duke Yonge (1814—1879) in 1839 in Brussels. Meanwhile, Henrietta had married John Martin Müller in Edinburgh. They had a daughter Theodosia Yonge Müller, born in 1839, but Henrietta died the same year, only three months after her mother’s third marriage. Theodosia Yonge Müller was the only grandchild of Alexander Mercer to have children, and it is through her that the last of his line descends.
The youngest son was Henry Courthose Mercer (1790—1820). He joined the Royal Navy, being commissioned a Lieutenant on 17 March 1810. He then served on a wide variety of ships, including the Plover, Hermes, San Josef, Queen Charlotte, Tonnant, Manly, and Puissant, before gaining his own command of the Badger, a revenue cutter patrolling the English Channel for smugglers. An account of their chase and capture of the Iris, laden with smuggled brandy, gin, tea, and tobacco is included in The Fine Art of Smuggling: King’s Cutters Vs Smugglers, 1700-1855, by E. Keble Chatterton. That was in November 1819, and a year later he died at Dover after a short illness.
In the ten years after Waterloo, Alexander Cavalié’s father died, as did his wife, and all three of his brothers. Robert Pocock, who was instrumental in renovating Mercer’s grave, is working on a biography of him and hopefully we will hear more of his story when it is published.