Haddock was born into a distinguished navy family. His grandfather, also Richard Haddock, had been rewarded by the government in 1652, having held commands under both
Charles I and subsequently the Parliamentary regime; he commanded the
Victory in 1642, the
Antelope in 1643–44, the
John in 1644 and the
Unicorn in 1648. In 1652 he served as Vice-Admiral commanding the
Vanguard. His father, William Haddock, also commanded trading vessels, and was appointed on 14 March 1651 to command the
America, a ship hired by the
Commonwealth of England Navy. He served in the
First Anglo–Dutch War and saw action in 1653. For his services he was awarded a gold medal. William initially lived in
Deptford but subsequently moved to
Kent. He had a number of children, several of whom followed him into the navy, including his son Richard. ==Command==