Born in Milford Haven, Pembrokeshire, Wales, Davis started out in piracy on 11 July 1718 when the slave ship Cadogan, on which he was serving as a mate, was captured by the pirate Edward England.

Here Davis was imprisoned on the charge of piracy, but was eventually released and sought shelter in the pirate den of New Providence in the Bahamas.

With New Providence being cleaned out by Governor Woodes Rogers, Davis left on the sloop Buck and conspired with six other crew members, who included Thomas Anstis and Walter Kennedy, to take over the vessel off Martinique.

[1] A clever and charming man as he was, Davis pretended to be a legitimate privateer to deceive the commander of a Royal African Company slaving fort in Gambia.

He once seized a more powerful French vessel by flying a black pirate flag from another large but lightly armed ship he had recently taken.

Howell Davis makes a minor appearance in Ubisoft's 2013 game Assassin's Creed IV: Black Flag, where his ship is tracked by protagonist Edward Kenway, who is seeking Bartholomew Roberts.