[10][11] In 1898, after returning to England, he was appointed Garrison Adjutant at Dover, and in November embarked for South Africa with his fellow Irishman General Sir William Butler, as Assistant Military Secretary.

He returned to the regular rank of captain in his regiment on 12 December 1901,[13] and served in South Africa until the end of the war, when he left Cape Town on board the SS Walmer Castle in late June 1902,[14] arriving at Southampton the following month.

On his return to England he received a brevet promotion to lieutenant colonel in the South Africa honours list published on 26 June 1902,[15] and abandoned regimental soldiering in favour of a staff career.

[16][6] From October 1902 to 1904, he served as deputy assistant adjutant-general (DAAG) with the 2nd Division, 1st Army Corps,[17] and on 28 November 1903 he received the substantive rank of major.

[27] On the outbreak of the First World War in August 1914, Bulfin and the 2nd Brigade were transported to the Western Front as part of the original British Expeditionary Force (BEF).

[28] He proved a capable corps commander, leading his formation through Ottoman defenses at the Third Battle of Gaza, opening the way for the capture of Jerusalem.

[37] In the summer of 1920 he was offered the job of Chief of Police and Head of Secret Intelligence in Ireland based on his loyalty to the Crown, his Irish origins and his swift handling of the nationalist unrest in Egypt in 1919.

[40] He died of heart failure at the age of 76 at his home in Boscombe, Bournemouth, Dorset, on 20 August 1939, shortly before the beginning of the Second World War.