A series of spinoffs of either the European-Turkish wars or the Napoleonic Wars, depending on how you look at it. Since the late Middle Ages, a number of city-states centered themselves on the "Barbary Coast," stretching from Morocco to Libya, based on a two intermeshed activities: piracy and slavery. These were collectively called the "Barbary Corsairs."
This was no small matter; pirate raids reached as far away as Iceland, and over the centuries millions of people were captured and sold in North African slave markets. Large parts of the European Mediterranean coast were uninhabited due to the danger of pirate raids. During the early modern era this trade was steadily becoming less respectable. However, Europeans throughout this era were too busy fighting each another, and the pirates did not present a military threat, merely preying on isolated and undefended coastal settlements. When a European frigate would appear, they fled. Every once in a while one of the larger powers would be sufficiently annoyed to send a fleet to punish them, but on the whole the smaller powers and even the larger ones had neither the time nor the money to deal with them once and for all.
In the 1780's a new nation known as America came to be. The Barbary pirates, thinking it vulnerable, began to prey upon its commerce and demand tribute. The Americans were not in the mood for this and sent a series of punitive expeditions. America was short on naval resources at the time, and was hard put to it, but nevertheless it did well enough. This was interrupted by the War of 1812. After this, another American squadron came to visit the Barbary Coast. Once The Napoleonic Wars were over, the Great Powers were free to send their own forces as well. First was the Royal Navy, and then finally the French, who conquered the Barbary Coast in 1830, ending the pirate raids for good.
These conflicts have been almost entirely forgotten in modern times, given other major events taking place around the same time which overshadowed themnote . Perhaps the only reason it is even slightly remembered at all is a single line in the US Marine Corps Hymn (the bit about "the Shores of Tripoli"), referring to the Marines' contribution to this conflict, which included an overland march from Egypt to lay siege to the city, as well as a daring raid on the captured USS Philadelphia to rescue her officers and burn the ship to deny it to the Tripolitans. Even then, most Americans have no idea what this line actually means.
