This is an antique Japanese military sake cup, decorated with a picture of the front of the battleship Nagato - then the flagship of the IJN, firing its main guns. The words on the back are "Showa 12th Year Lookout Competition" "19th Destroyer Squadron". The words in the middle of the back are "Pure Tin" and the maker's mark.

I'm guessing this is an annual lookout/search/watch competition held for ships, and that the 19th destroyer squadron won the competition among the different squadrons. The cup comes in original wooden box with the maker's stamp on the lid.

Size: 3" across

Condition: Mint