Ghelimede
Ghelimede is a fantasy world which has recently entered its colonial period. The discovery of a hitherto unknown 3rd continent on the planet's southern hemisphere and the recent decline of what had been the preeminent naval power in the world have provided big opportunities for the two global powers still standing to expand their fortunes and holdings.
This new world is also a land of opportunity for pirates. Following a wide sweeping naval treaty signed by the major seafaring powers-that-be 10 years ago which explicitly outlawed the use of privateers, the colonies suddenly found themselves host to a veritable armada of well trained seafaring raiders suddenly no longer able to plunder under an (admittedly thin) veil of legitimacy. The end result was the pirates going into business for themselves and ultimately, the founding of an informal (but rapidly becoming influential) pirate republic nestled somewhere in the islands off of the new continent.
The pirate "kingdom", if you will, enjoys a complicated relationship with both the developing colonies and their patron empires. On the one hand they are a principle source of crime and a direct threat to trade in the region; on the other, given their quai-legal ad hoc community, the pirates have also become an indispensable under-the-table trading partner for the fledgling colonies which helps them survive with goods and services they would otherwise have difficulty obtaining where they are.