Ellesmere was appointed a captain in the part-time 3rd (Edinburgh Light Infantry Militia) Battalion, Royal Scots, on 10 March 1894.
The battalion was embodied in December 1899 and in early March 1900 left Queenstown on the SS Oriental for South Africa to serve in the Boer War.
[1] Lord Brackley and most of the battalion left Cape Town for the United Kingdom in early May 1902, shortly before the end of the war.
[2] After his return, he was appointed Aide-de-camp to Sir William Knox, Commander, Royal Artillery, for 3rd Army Corps.
They had seven children:[4] Ellesmere sold his father's seat, St George's Hill House and its 964-acre estate to master builder W. G. Tarrant, who went on to create Surrey's landmark St George's Hill estate.