it's a simple cudgel.
The most basic would be: get a solid piece of branch - between 1.5-2 inches in diameter : 2.5-5 cm - this depends on how strong your are and how large your hands are.
remove the bark and nodules (penknife is all you need), round out the slimest part for a handle and that's your cudgel. I like mine around 2-3 feet in length: 60-90 cm.
A more advanced cudgel would have you drill a hole in the end of the handle and add a leather wrist thong.
Stops you losing the club and also can be used to swing the club with suddenly extending the range and taking an opponent by surprise.
Further enhancements include wrapoping the handle with leather for a better grip. Studding the head with nails or studs.
Me I just like a shaped piece of seasoned hardwood and a wrist strap.
I made something similiar but shorter for tint a few years back. This would me a lot more advanced as it was turned on a lathe.
Hmm thread is still there but club pic vanished. I'll check my computers....
(some time later)
Nope can't find it. IF you read this tint and you still have the club - post a picture
I think I also made one for someone else with a thinner shaft and a rounded end. No idea who but someone on the forum lol