I love playing around with the idea of pirates in my hometown. (One story already I'm working on involves such.) Louisville, Kentucky actually was a major and important shipping stop in the early history of the country. Up until the creation of the Portland Canal and then the McAlpine Locks all river traffic had to stop in Louisville. So I was playing around with alternate history settings where pirates might naturally have developed in this city. Here's what I came up with, from what little I remembered of Kentucky History from middle school (feel free to use it, I don't have the patience for alternate history research and writing, I'll wave the share-alike for this idea if you want):
The French-Indian War goes badly for the British Colonists. Britain says they'll send more support, but fail to do so. What little government there is of Kentucky swings to support the French. (This was actually considered more than a few times. Kentucky has long had a history of being extremely libertarian, and spent a long amount of time examining the offers of joining both the Spanish and the French colonies before deciding to be the 15th State.) The few British fighting for the Ohio Territories, sandwiched by the French and French supporters probably either die off or surrender. British currencies stagger and fall in the Colonies as a lot of trust is lost between the British and Colonists, the French currency becomes the defacto standard in North America. Assuming that New Orleans, the southern "capital" of French Colonization, and Montreal, the "northern" capital, become large banking centers of North America, there would be an awful lot of cash and goods flowing from Fort Duquesne (previous Fort Prince George, in our history later became Fort Pitt, and now Pittsburgh) to New Orleans via the Ohio river. Louisville makes perfect sense for something of a median banking center between Montreal and New Orleans, probably in the Portland area (now a part of Louisville, although once its own city). Not to mention that Louisville wouldn't even need a name change, being named after King Louis the XIV.
With all of that set up you just need some poor Kentucky British patriots, and/or perhaps a group of Spanish Floridians looking for a quick buck and/or ways to destabilize the North American French economy. There you have it, Pirates. Keep in mind, Kentucky's just the kind of place that would turn pirating not just into an enterprise, but into lucrative semi-legal business. Kentucky is a spiritual home to the finest sin industries in the country: big liquor, tobacco, big money gambling (no slots here, but let me introduce you to this thing we call the trifecta). Supposedly the current cash crop for the State is Maurijuana (and no, its not legal here) and most of the farmers losing money on tobacco as supposedly switching to it.
I just love the image of some Kentucky banker (read: bastard), working for the Bank of New France's Portland, KY branch, sipping on fine Kentucky Bourbon poring over ledgers and complaining about pirates. Give it a few decades after the French-Indian War and you could set this particular scene in the Kentucky Giant Jim Porter's Shippingport bar The Big Gun Tavern. How's that for a set of initial characters and locations?
It would be really cool to see someone take this idea and run with it. There are some interesting possible directions to take it. Would the British have helped us fight a war of independence from France like the French helped America win the war of independence from Britain? Or would the French happen to be a more fair and laissez-faire governor and such a war never happen? Suppose that the French call for a prohibition (as a measure to cut at the pirates, perhaps?) would the pirates take up Bourbon smuggling? What systems would the pirates use: secret codes, fraternal greetings, meeting places, ship storage? What happens to George Washington in this alternate history? How does the balance between Spanish, French and British colonies ultimately play out in such an alternate history? What happens to the Indians (Native Americans)?
If anyone feels taking this idea seriously I do have some resources to recommend, even if I don't have the patience to research this stuff myself.