Inherited 30 caliber Luger - Help with Markings and Origin

[kdcarver]

Several years ago I inherited a luger from my grandmother. She told me it was brought back from WWI by her uncle Don who served during that war. I've never shot the gun, but will get it serviced by a local professional gun shop in hopes of being able to take to the range on occasion.

I'd like some help with the meaning of the markings on the gun and holster to see if I can get some history about it's origins. If anyone can help, I'd appreciate it.

The gun has a holster that is in deteriorated shape. There is a stamp in the leather on the backside of the holster that reads: "149" in a box and "B.D. III 1915" another box.

On the pistol there are the following markings:

On the top of the slide action: "DWM" in a script font.
On the underside of the barrel: "2297" and either an "e" or "l" in script font.
On the body, under the barrel, in front of the trigger guard: "2297 GERMANY" and either an "e" or an "l" in script font.
On the left side of the body above and in front of the trigger: A crown and the letter "N".
On the back of the gun above the grip: "97"
On the bottom of the magazine: "GERMANY"

The barrel measures 75mm from muzzle to the body, 90mm from muzzle to the extractor opening.

The grip appears to be made of wood, and is "checkered". The magazine plug appears to be wood as well.

The caliber is .30 based on the cartridges that were in the magazine when I received the gun.

Any help in understanding the markings so I can have an idea of where the gun was manufactured, and when, would be appreciated.

Thanks!
Kirk