http://imgur.com/a/koKSY Here are some pictures of the bayonet and serial numbers on it. There is also a "b" at the very tip of the scabbard.
I think it's German and from World War I, but I'm just guessing. Any info on it would be greatly appreciated.
I'm pretty sure that's a Brazilian M1908 bayonet. If you could measure the blade length or the diameter of the muzzle ring, It would be easier to identify.
Edit: for clarification, if it is indeed a M1908 bayonet, it would have been made in Germany from 1908 to 1914, so along the lines of what you were thinking.
As /u/borund said, it would appear to be a Brazilian Model 1908 bayonet. Measure the blade. It should be 11 3/4 inches long.
They were built by Weyersberg, Kischbaum and Co. in Solingen, Germany. They made a number of blades for South American contract Mausers, not just Brazil.
I don't believe it's WWI German. The Germans were very good about marking their blades with the company who made them. That looks like some sort of middle eastern writing on there. Can you post some more pictures, especially where the bayonet would engage the bayonet lug on a rifle? Are there any other markings on the blade? It's certainly a nice old bayonet, and likely pre WWI.
