In 1901 John lived in house 82, Vergemount Hall, Clonskeagh, Pembroke West, Dublin with his parents and 3 siblings, Albert George; Ernest Hill and Hilda Joy.
The 1911 Irish Census records the family living in house 1, Clareville Road, Terenure, Dublin. His sister Hilda Joy is the only sibling living at home. John’s occupation is described as a Banker.
Scott served with the 1st Bn. Prince of Wales's Leinster Regiment (Royal Canadians).
On 1st July 1916 Scott was promoted to 2nd Lieutenant (on probation).
His first theatre of war is recorded as Salonika, Greece from 15th September 1916.
On 2nd August 1919 Capt & QM Lt J M Scott returned to the UK with the 1st Bn Leinster Regiment.