@paco I'm afraid you didn't check the pirate's special ability (pirates, not blackbeard):
"Settler Units cannot be trained or purchased, but you can capture other civilizations' Settlers" (the ability is longer)

See https://forums.civfanatics.com/threads/new-civ-game-guide-republic-of-pirates-tides-of-power.700455/

@paco it's all about "practicing" at the end ;).
#OneMoreTurn

@paco congrats, enjoy your achievement :D.