My reading of the volume of Lovecraft’s letters to Bloch, now completed, has helped fill in a gap in the life of Arthur Leeds. On page 274 Lovecraft gives Kenneth Sterling a potted biography of his friend Leeds, and notes that…
During the war he was a volunteer with the Canadian Army … he has travelled extensively, even been to Egypt.
This new (to me) data helps fill in the circa 1916-1919 gap for the Leeds biography, as found in my book Lovecraft in Historical Context #4. Leeds was Editor of Scripts at the Edison movie studio in New York City until December 1915, so any war service presumably started (after basic training) in late spring 1916.
Presumably he embarked for France. The Canadian Corps. of volunteers was “one of the most effective allied fighting forces on the Western Front”, and if he was serving with them in an armed capacity he would have seen some heavy fighting in trench warfare conditions.
As for Lovecraft’s mention of Egypt, one wonders if Leeds headed there for a few month in late 1918/early 1919 on being demobbed? It would make sense to go somewhere both warm and safe (Egypt was then British) if one had the meagre funds to get to southern France and then by ship across the Mediterranean. Rather than return home to face a possibly brutal New York winter with no prospect of employment — the old New York movie industry had upped stakes and ‘gone west’ to California. Edison formally wrapped up its Bronx movie division in 1918.