Brothers John and Mark Sweny were respectively the eldest and second sons of Eugene Sweny, a chemist who practiced on St Mary’s Street in Dublin. Captain Mark Halpen Sweny (1783-1865) was a naval officer who fought under Captain James Morris at Trafalgar in HMS Colossus. This ship was stationed in Admiral Collingwood’s lee column and although engaged at the same time by three enemy ships of a similar size, was successful in defeating two of her adversaries, the French Swiftsure and the Spanish Bahama. Mark, who had joined the Royal Navy as a 1st Class Volunteer, soon became a midshipman and then a lieutenant. In contrast, his older brother, Major John Sweny (1778-1841), had worked his way through the ranks in the cavalry and attained the rank of sergeant major in the 4th Dragoon Guards. He had thereafter gained a captaincy in the King’s Dragoon Guards (KDG) by purchase in 1805 and his first job was as regimental adjutant before taking command of a troop at Waterloo.
The two brothers not only fought in Britain’s most important sea and land battles, they both also met Napoleon Bonaparte. The first to encounter the French emperor was John at Waterloo where he was the KDG’s 4th Troop Commander. The then captain went further than most of his regiment, and the British heavy cavalry, in their first and greatest charge at that battle, penetrated into the enemy’s rear areas. Here he was captured having sustained seventeen lance and sabre wounds. On being brought before Napoleon for questioning, Bonaparte was reported to have ordered his surgeon to save Sweny’s life as he was suffering from an immense loss of blood. Some months later, Napoleon, when travelling on his prison vessel HMS Northumberland en-route to his second and final exile on Saint Helena, recognised John’s image in that of his brother Mark who was a lieutenant on board the ship. When playing chess with Sweny, Bonaparte, who apparently had a great memory for faces, commented that he was sure he had met him before but he had been wearing the dress of a British army officer. Once they had discovered their connection through John, Bonaparte was reported to have commented, ‘Such are the vicissitudes of life, your brother was my prisoner, and I am now yours.’
By Richard Goldsbrough