The Pokemon world had issues with pirates operating off the Poke-Barbary Coast. Routing them wasn't worth the effort, so most nations just paid off the pirates to leave them alone. Unfortunately, the wealth disparity between nations made this increasingly difficult since Galar could afford to price everyone else out, which meant it was more cost-effective for poorer nations to just pay to have Galar ship their goods instead of being able to ship them independently.
This all changed after Unova got independence from Galar and obviously lost their free shipping privileges. But Unova wasn't about to go crawling back to Galar's navy for shipping in the Barbary Coast and they couldn't afford to pay the extortion, so instead Unova just kicked in the door to Poke-Tripolitania and told them to knock off the shit since it was an open secret that that the "pirates" were mostly government-funded privateers. This was significant because Unova was a brand new country with a barely-existent navy and was considered a joke among the other powers. But if Unova could humiliate the Barbary States, then it showed nations like Kalos and Paldea could walk all over them, and they did, ending the Barbary Pirate extortion racket.
Most of the aggressor countries were happy to just blow shit up, drop their balls on the negotiating table, and leave having made their point. But Kalos decided to outright conquer Poke-Algiers, turning it into Kalosian Algeria and allowing free trade between the mainland and its African colony.
tldr, black people from Kalosian Algeria have been living in Kalos for over a century. It was more common there than in other Poke-European nations.
