Although much of his life and career is unknown, he is recorded in A General History of the Pyrates, which states "He was brave in his Person, courteous to all his Prisoners, lived beloved, and died regretted by his own People.

He raided French fishing fleets in Newfoundland and later sailed to Fayal in the Azores and then to the Canary Islands where he attacked Spanish ships en route to Barcelona during 1704.

As he made his way around the Cape of Good Hope, putting into the Bay of Saint-Augustin for water, wood, and other provisions, Halsey picked up several castaway sailors of the lost Degrave, formerly under the command of Captain Young.

It fired a warning shot towards the Charles which injured a crew member manning the wheel as well as unstripping the swivel gun and severely damaging the topsail.

Setting sail for Mocha, he encountered a British squadron consisting of five warships shortly after entering the Red Sea in August 1707.