Alexander Thomson Cruikshank was born at Prahran, Melbourne in 1865. He was the third child of Samuel Cruikshank, a carpenter and joiner, and his wife Jane Thomson, both of whom had migrated from Scotland. He was employed as chief clerk and later accountant for Messrs L Stevenson and Sons, warehousemen, in Launceston, from about 1890. He joined the accounting firm of Rolph & Young in 1902. He became a senior partner with Gordon Creasey from about 1906 until his death in 1934. Alexander was a member of the Tamar Rowing Club; the Launceston Lodges, Perfect Unanimity and Lodge of Hope; the Northern Club and Launceston Club. He owned racehorses and Collie dogs, raced greyhounds and had a passion for antiques. He was warden of the Launceston Marine Board and a member of the Launceston Rotary Club.
Alexander married Mary Hyland Germaine on 2 Nov 1896 at Mentone, Victoria. Their first child Blanche was born in 1900 but died aged 16. Their son Samuel was born in 1902. By 1920 the marriage had ended and Mary moved to Hobart and later Melbourne with her son. Alexander died on 10 Jan 1934 and was buried at Carr Villa after a funeral at the Masonic Temple in Brisbane Street.