Holy Shit, the Third Punic War!

 The Third Punic War started in 149 BC, and by 146 BC, Cato the Elder saw his dream of a dead Carthage fulfilled. If you were a Carthaginian at the time, the whole thing was just...such bullshit. You're sitting here in your utterly defeated country, doing whatever the Romans tell you to do because they could burn you and everything you love as easily as you could punch a rock.

Not that I'd recommend it. Rocks just aren't very good at dodging.

Then some foreign tribes started raiding Carthaginian territory. Carthage was bound by treaty to arbitrate all conflicts through the Roman Senate, but at this point they had paid off the war indemnity and considered the treaty dissolved. The Romans saw things differently.

More importantly, the Romans were facing a huge increase in population and a huge staying-the-same of farm yields. So the Third Punic War, essentially, was Rome looking at Carthage and saying, "Hey, guys, we need your food...so..." then lighting North Africa on fire.

Not the farms, though. Boy, would that have ever been awkward!

Carthage was destroyed. Utterly. It's buildings were burned and its people put to the sword or sold into slavery. Its territories were annexed by Rome, and the city itself would only be rebuilt (as a Roman city) a century later. Then it became a Vandal Kingdom for a while until it was conquered by an Islamic Caliphate.

But here's the thing: when you completely obliterate a city, there's no one around to sign a peace treaty. In a weird but arguably (technically) legal way, the cities of Rome and Carthage remained at war after Carthage ceased to be part of the Empire. At least, that's how officials from both cities saw it in 1985, when the mayors of both cities signed a peace treaty and symbolic declaration of friendship.

If you take that technicality at face value, the Third Punic War was the longest conflict in history, lasting over 2,130 years.

Holy shit.