His Attestation Papers indexed provide more detail. Full name Walter Roy Culbertson, born November 26, 1888. The front of his form has been scanned and it shows that he was born in Cornwall Ontario and is single. He's a salesman and gives his father's name as James J. Culbertson, also residing in Cornwall.
Walter enlisted on 8 October 1917 in Kingston Ontario.
See http://www.smeaton.org/Eamer_Detailed_Genealogy.pdf p. 113 for more details on the Culbertson family. Walter Roy's parents were James Culbertson and Laura Gallinger.
In November 1922 Walter married Catherine Graveley in Cornwall [Source: 019259-22 Walter Roy CULBERTSON, 33, Clerk, Cornwall, Cornwall, s/o James G. CULBERTSON & Laurie GALLINGER; married Catherine Grace GRAVELEY, 34, Cornwall, Cornwall, d/o Walter GRAVELEY & Catherine MACGILLIS; witn Walter GRAVELEY & John GRAVELEY, both Cornwall & Isabella McGILLIS, Harrison, 6 Nov 1922, Cornwall on http://homepages.rootsweb.ancestry.com/~maryc/sdg1922.htm]
What happened to Walter?