 He was promoted to lieutenant in 1889, captain on 26 November 1892, major on 11 October 1902 and lieutenant colonel in 1906.Davidson-Houston was assigned to the British South Africa Company Police, and was assistant commissioner in Mashonaland (1890–1892).He was assistant inspector of Gold Coast Hausas (1894) and captain of the West African Frontier Service, Kwahu (1894–1895).