Source: September 1916 K.I.A.
Family Search: Private Walter George Gunn was born on 11 October 1879, in Bristol, England, United Kingdom as the son of John Gunn and Elizabeth Gunn. He immigrated to Canada in 1913. He registered for military service in 1915. In 1916, his occupation is listed as labourer. He died on 27 April 1916, in Poperinge, West Flanders, Belgium, at the age of 36, and was buried in Poperinge, West Flanders, Belgium.
This labourer joined the 39th Battalion at Lindsay, Ontario on January 17, 1915. He was 35-years-old and single, with a brother from his home town of Bristol, England.
Boarding a troopship, he arrives in England on July 3, 1915, and is based at Shorncliffe, Kent. It appears he went AWL for 4-days as he forfeited that amount of pay on the 23rd of that month, probably going to see his family.
He did not have to wait long for active duty, as he was transferred to the 18th Battalion on September 10, 1915, and headed overseas to the Battalion on the 14th.
History of the 18th Battalion CEF, "The Fighting Eighteenth" 