Captain Ward and the Rainbow, or Ward the Pirate (Roud 224, Child 287) is an English-language folk song. It recounts a tale of the pirate Captain Ward, likely Jack Ward.
The king sends a ship, the Rainbow, after Captain Ward. In one variant, the ship carries 500 seamen, in another it carries 1,300. Ward defeats the Rainbow and sends taunts back to the king, "If he reign king of all the land, I will reign king at sea." In many variants, Ward claims to have never harmed an English ship.