Thomas was born On This Day April 17th 1891, the only son amongst three children of a Stock Exchange worker, also named Thomas Nicholson, and his wife, Mary Jane. In April 1904, two days before his thirteenth birthday, he joined the College, having previously been at the Prep. His time at Dulwich would last for the next three years, until he left in summer 1907, at which point he was in the Modern Lower Fourth. In 1910 he joined a firm of shipbrokers, McCulloch & Boyd, with whom he was employed for the next six years at the Baltic Exchange.
In August 1916, two years after the start of the war, Thomas enlisted for military service, as a member of the Army Service Corps. He subsequently spent several months training in England, at Aldershot and Bulford, before being sent out to Salonica, Greece, that October. Upon his arrival he was attached to the 802nd Company of Mechanical Transport and served with his new unit through that winter and into the following summer. In August 1917 he fell gravely ill with what turned out to be dysentery, ultimately succumbing to the illness on August 17th whilst at a Canadian Hospital in the town of Salonica itself.