Shackleton, Francis Richard (‘Frank’) (1876–1941), Dublin Herald of Arms (1905–7), was born 19 September 1876 at Kilkea House, Kilkea, Co. Kildare, second son of Henry Shackleton and Henrietta Letitia Sophia Shackleton (née Gavan). His elder brother was Sir Ernest Shackleton (qv). Like his brother, he attended Dulwich College (1891–3) after the family moved to England, and in October 1899 was appointed assistant secretary at the office of arms at Dublin castle. In 1900 he volunteered for service in the second Boer war and was commissioned as a second lieutenant in the Royal Irish Fusiliers, being promoted to full lieutenant in October 1900. He was invalided home in 1901, and in 1903 served as Gold Staff Officer during Edward VII's visit to Ireland.
Of a dapper and flamboyant nature, he moved in society circles and was acquainted with the duke of Argyll and Lord Ronald Sutherland-Gower. He was also an intimate friend of Sir Arthur Edward Vicars (qv), Ulster King of Arms and knight attendant on the Order of St Patrick, and in 1907 the two men shared a house at 7 St James's Terrace, Clonskeagh. Vicars, who ran the office of arms as though it was his own private kingdom, secured an appointment for Frank Shackleton as Dublin Herald in September 1905. While serving in this capacity, he was suspected of involvement in the theft of the regalia of the grand master of the Order of St Patrick, commonly known as ‘the Irish crown jewels’. The jewels were taken from the safe in the office of arms in the Bedford Tower of Dublin castle sometime between 11 June 1907, when they were last seen, and 6 July 1907, when the theft was discovered. Some other regalia of the order, and some private family jewellery, were also stolen. The break-up value of the Irish crown jewels was estimated to be around £5,000 but as historic pieces of jewellery they were worth much more. Shackleton was known to be living well beyond his means and soon became the focus of the police investigation. Rumours circulated that he had taken the jewels to the Continent to be broken up, but no actual evidence could be found against him. Edward VII, who visited Ireland in 1907, was furious at the theft and called for the resignation of all employed at the office of arms. Shackleton resigned as Dublin Herald in November 1907 but cooperated fully with the viceregal commission appointed to investigate the theft in 1908. While nothing was ever proven against him, he remained the prime suspect in the case and Vicars, in his will of 1920, referred to the incident as ‘when I was made a scapegoat to save other departments responsible and when they shielded the real culprit and thief, Francis R. Shackleton’ (Huntford, Shackleton, 683).
In later life Shackleton was associated with several dubious business deals, being declared bankrupt in 1910 with debts of nearly £85,000. He fled to Portuguese West Africa, where he initially worked as a plantation manager but was arrested in October 1912 on fraud charges and sent back to London for trial. Charged with the fraudulent conversion of funds entrusted to him by a Miss Mary Browne, he was found guilty at his trial at the Old Bailey in October 1913 and sentenced to fifteen months' hard labour. On his release from prison he assumed the surname ‘Mellor’ and his brother secured him a position in a London office. Little is known of what he did for the next few years, but by 1934 he had moved to Chichester, Sussex, where he opened an antique shop. He lived at Chichester with his unmarried sister, Amy Vibert Shackleton (1875–1953), for the rest of his life. He died at St Richard's Hospital on 24 June 1941 and was buried, under the name of Mellor, in Chichester cemetery.
The Irish crown jewels were never recovered. In 1927 a Parisian jeweller made overtures to the Irish Free State government, offering to sell them back. This offer was declined. In 1928 the wooden brass-bound box that had held the jewels was sent to the office of arms without any letter of explanation.