Having trouble identifying this pin.

[RDUNE]

I found this in a box with a couple other imperial items a while back. I'm having trouble identifying it. I've google searched, and forum searched, and I'm coming up with nothing. I would really appreciate any help.

Thanks,

-Ryan

[HPL2008]

Unless I am much mistaken, the monogram is the regimental cypher for Infanterie-Regiment Nr. 125.

(See Infanterie-Regiment )

The regiment was raised in 1809, so, judging from the 1809 / 1909 dates, apparently, this is a badge related to its 100th anniversary.

[RDUNE]

Thank you HPL2008, I really appreciate your help