Monkey Country

This isn't some sort of racist nickname, they are actual monkeys! I understand your reaction to the name, for I have felt the same way when I first heard it. The explanation sounds like a dumb joke or ravings of some madman - who in their right mind would believe in monkeys forming a functional country with its own government and army? Turns out, the stories are true.
There are a few islands ruled by no one but monkeys. Those monkeys have their own leaders and a complex social structure, a standing army (standing as straight as they can), monkey-craftsmen and monkey-peasants. They even have sailboats and monkey-sailors! Really, a gimmick parody of humanity that, some argue, shows well how our civilisation looks to the outsiders. The only thing that have failed to imitate so far is our speech, although writing (mostly nonsense) has apparently proven somewhat easier.

History

Perhaps unsurprisingly, this whole thing started with a bunch of hyperactive scholars out to prove their opponents wrong. Something about an audacious theory that us humans are related to monkeys, and therefore monkeys have just as big of a potential as a species. So they arrived on a godforgotten island in the New World where many monkeys were sighted, paid locals to set aside a piece of piece of land and started their experiments.
Apparently the monkeys were very smart, and mimicked humans' behaviour well. Very well. Soon they knew how to make primitive tools, row boats and started learning agriculture. However, some things they learned from your everyday colonists were...not so peaceful. Before scholars realised, the monkeys have formed a social structure resembling that of a noble-peasant system, stole some weapons from the settlers and formed an army. Monkeys then got scholars of their own and started developing their crafts, making bows and spears and even some sort of crude uniforms for their soldiers.
Naturally, the settlers were not amused with the outcome of such experiment. But what could they do? Monkeys outnumbered humans 10-to-1 on this island alone, and grew in numbers so quick it was soon 20-to-1. Attacks and burglaries became increasingly common. Several punitive expeditions were launched (to varying effect), but in response monkeys have placed traps all over the island and fully embraced the guerilla warfare. After a few years the settlers have given up and decided to leave, but it did not stop there! The monkeys followed them as well, sailing to nearby islands and forcing their rule onto the local monkey tribes (clans? communities?), as most countries tend to do.