The Skeleton Slave Trade was a massive foundation, which started at the very beginning of the war for the treasure, and ended at the battle for Pyrate's Cove.
It began, when many unfortunate sailors would lose their ship, over the dreadful Captain Dreadeye and ended up stranded on Pyrate's Cove and nearby islands. They were captured by the Skeletons, and enslaved. The head of this foundation was the Skeleton, Terror Keeper, who was thrown into the Ship's hole, by Admiral Blue Beard and Dagger Tremaine at the Greater Black Sea Battle. He was later replaced by Agememnon, who from then on, was depicted with a whip. The heart of the slave trade was always Pyrate's Cove, and when Agememnon had discovered the abandoned Prison Island, which was named Skeleton Crew Prison, he made that the place where slaves were kept, while Skeletons discussed whether their fate was to be sent to the Phantom, or Pyrate's Cove. Until, Privateer, Provost Parel led an attack on the Island, and burned it down.
Eventually, most of the slaves escaped Pyrate's Cove. But some were still imprisoned. Until Captain Cutlass battled against the Skeletons and won, freeing the remaining slaves. This marked the end of the Skeleton Slave Trade.
This was made up by Baginman.