I am curious if are there any wars still going on because of anomalies of diplomacy like the following examples:
Rome vs. Carthage, 264BC - 1985AD,
Since Carthage was destroyed, there were no official peace until Tunisia and Italy signed one.
Montenegro vs. Japan, 1904-2006,
Montenegro joined up into the conflict between Russia and Japan, but in the meantime lost it's independence and no peace was signed until Montenegro gained it's independence back.
It is fun to read the others, here is the link to the page.
I can see Costa Rica is legally still at war in the first world war with Germany because of legal issues of Costa Rica's government back in time. Second example is Italy vs Japan. In the last days of second world war, the allies' occupied Italy declared war on Japan, but never signed peace between them. Are there more?
To be precise after two answers: I am looking for examples where the peace was signed, but for some reason somebody didn't participated or it isn't valid.