Military Coat

This is the last post.... I think this one has me the most intrigued. This coat is wool and it's extremely heavy! I'm in the dark on this one, and I'm hoping someone can help me. I think the biggest clues may be the buttons and the marks that are inside the coat by the inner pocket. Can anyone tell me what the marks indicate? This one is has kept me up at night trying silver the puzzle of it's origins.
Thanks for any help! (If you know of a good website that has info on this stuff please direct me there so I can stop hogging up the feed, lol.)