It’s called The Amazing Remarkable Monsieur Leotard:

My pal Dan Best worked with me on the story. You may recall him from the Escapist piece we did for Dark Horse a couple of years back. Leotard is a huge sprawling epic that gobbles up a large swathe of history from the Franco-Prussian war to the sinking of the Titanic
My book tour will not be quite so epic, but will impress nevertheless, starting in July with San Diego, where I am a guest of the convention, and finishing with an appearance at Page 45 in the UK on the first Sunday of August, with a couple of other stops in between, still to be worked out and announced here in due course.