In July 1703, Governor Joseph Dudley of Boston sent out Captain Daniel Plowman of the Charles with a privateering license to attack French and Spanish ships off the coast of Newfoundland and Arcadia.

Before leaving Marblehead, Massachusetts, the Charles's crew under Quartermaster Anthony Holding mutinied and locked the ailing Plowman in his cabin.

The crew plundered nine Portuguese ships off the coast of Brazil and gained a large sum of money,[2] even though England and Portugal were at peace at the time.

[3] As a result, The Charles contained large amounts of Brazilian sugar, hides, cloth, guns, gold dust and coins with a value estimated at over £10,000 sterling (£2.01 million as of 2023).

[2] Within a week, Quelch was in jail because the Portuguese were not in his letter of marque and, more importantly, Queen Anne and the King of Portugal had become allies.

"[4] Following their conviction, on Friday, 30 June 1704, the pirates were marched on foot through Boston to Scarlet's Wharf accompanied by a guard of musketeers, various officials, and two ministers, and following a silver oar, the emblem of the Lord High Admiral.

The origin of this myth of Quelch's flag being described as having "in the middle of it an Anatomy with an Hourglass in one hand and a dart in the Heart with three drops of Blood proceeding from it in the other.