OK, not a British film, but the star was, and...............
I don't think there'll be one as early as this again - silent of course of Charlie Chaplin in WW1 making a fool of himself in the army and on the front line, with the usual comic German oafs. Also starred his half brother Syd.
I know there is a big divide of those who think he is comic genius and those film fans who he leaves cold. I sit on the fence, thinking the likes Harold Lloyd, Ben Turpin, Buster Keaton and L&H are far funnier.
The film jumps about a bit with chunks of it seemingly lost, but I did laugh a couple of times, and its only about 40 minutes long.