Thanks, Henryp and Kenny, the following website rather mislead me:

http://sangstories.webs.com/willyegotaeflanders.htm

What they state is obviously wrong.

However I still maintain that the song has got absolutely nothing whatsoever to do with the First World War.

The low countries Netherlands and Belgium can be accurately described and have been by those studying the history of conflict in Europe as the crucible of Europe certainly true for the last 600 years.