author
b. 1877
A Belgian military writer best remembered for books on the First World War’s Western Front, he wrote under the name Willy Breton. Library records identify that name as a pseudonym of William Henry Marsily, born in 1877.

by Willy Breton
Writing under the pseudonym Willy Breton, this Belgian author is associated with early 20th-century books about World War I, including La bataille de l'Yser and The Belgian Front and Its Notable Features.
The clearest biographical detail I could confirm is that Willy Breton was a pseudonym of William Henry Marsily, and that he was born in 1877. His surviving works suggest a strong interest in Belgium’s wartime experience, especially the Yser front and the broader story of the Belgian army during the conflict.
Reliable personal details beyond that appear to be scarce in the sources I found, so it seems best to remember him chiefly through his war writing rather than through a well-documented public biography.