After his education was completed  he took a commission as 2nd Lt in the 5th Essex territorials beforeresigning his commision in February 1913  his career took him to Canada where he met his future wife Helen.

On the declaration of war he enlisted with the 95 Saskatchewan Rifles who were among the first of the Canadian Contingents, gaining promotion to Sergeant.

In August 1915 he married Helen Blain of Regina, Saskatchewan at Chelmsford Cathedral.

In September 1915 we was given a commission the 12th Essex regiment and soon became attached to the 1st Essex as they left for the Dardanelles.

During this campaign he took the dangerous role of Bombing Officer for the 1st Essex

Marshall was killed in action on Christmas Eve 1915.

His two brothers were still serving officers - 2nd Lt R M Straight in 2nd Essex and Sub-Lt A H Straight RNR.