My nomination is Donald Jack, a Canadian humorist. I only discovered him recently, while trolling for works with a World War I theme. Jack is best known for his series of novels known as the Bandy papers, about a WWI ace named Bartholomew Bandy. The fans of Wodehouse and those who like to see WWI skewered will find much enjoyment here.
There are nine Bandy novels. I've finished the first three and have reached the end of the war, so next will be to find out what Bandy gets up to in the 1920s. Annoyingly, only the third, fourth and sixth novels seem to be available in ebook, but perhaps the Canadians have access to more of them. But I have to say that I ran the name of Donald Jack by a Canadian friend and she was clueless.