We really need someone fluent in Japanese. It’s not written in hiragana (the simplified phonetic Japanese lettering system) but in kanji, where each character represents a whole word… and there are thousands of them.
The only one I recognise is the one on the right which is 賞 and means “prize” or “award”. When acccompanied by a 牌 character (similar to but not identical to the one on the left) I think it would just clarify that the prize/award is in the form of a medal (as opposed to money, a diploma, certificate or whatever).
I don’t recognise the monogram below the eagle but, since it uses western alphabet, it’s unlikely to be war-related. I would think post-war and it might be sports-related, some kind of civic recognition or for an industry achievement. Without a full translation it will take some tracking down since it may well be something very specific of a local nature rather than a ‘national’ award. The translation might be more difficult if the inscription includes something like a company name.