Gordon subsequently held the position of Chief of the General Staff in the Australian Army before commanding a number of reserve formations during the First World War.

[1] At that time, while still a cadet, he met the future King of Spain, Prince Alfonso, who was in exile, attending the military school at Sandhurst.

Prince Alfonso was proclaimed King of Spain in December 1874 and received the news while he was dining with Gordon in London.

[2] He unsuccessfully tried acting, newspaper publishing, and being a merchant before joining the police force in Adelaide, South Australia in 1881.

[1] He was promoted to colonel in 1893 and became the Commandant of South Australia's military forces in the same year, succeeding Major General M.F.

[2] In 1900 he went to South Africa where he participated in the Second Boer War, serving as chief staff officer for Overseas Colonial Forces.

[1] He was regarded as an able and intelligent officer and during his service he contributed to the foundation of early Australian military aviation and the setting up of the Lithgow Small Arms Factory.