Mark James Rosser was born in Ballarat, Victoria, was single and a Butcher when he enlisted in the 24th Battalion, 6th Reinforcement on 12 July 1915 at the age of 19. His unit embarked from Melbourne, Victoria, on board HMAT A38 Ulysses on 27 October 1915. He was wounded by a shell explosion on 29 July 1916, resulting in his evacuation aboard the Hospital Ship Gloucester Castle to England. He re-joined his unit from hospital in March 1918 but soon found himself back in hospital, again wounded in action with a gunshot wound to the buttocks in 4 April 1918 and was invalided to France. This would mark the end of the war for him as the armistice was signed while he was still recovering. He travelled back to Australia on 28 March 1919.

His younger brother, Pte Ambrose Edmund Rosder, 2nd Machine Gun Bn, also served (Tree No. 2054)
Tree No. 1653