He was possibly born on 1 January 1761 in Boston, Massachusetts,[4] where his British father, former naval captain Benjamin Hallowell III, was Commissioner of the Board of Customs.

Her mooring cable parted and she was driven within range of Spanish shore batteries; Hallowell, ashore to sit at a court-martial, was denied permission to rejoin the ship and take her to safety.

She was subsequently wrecked off Monte Hacho in high winds during her officers' attempts to move to a safer anchorage, with the loss of almost 500 lives.

[11] Hallowell decided to return to reinforce Sir John Warren's squadron, but on 24 June Swiftsure encountered Ganteaume.

[11] On his repatriation, Hallowell received the court-martial that was automatic for a Royal Navy captain who had lost his ship, but was honourably acquitted.

But that that period may be far distant is the earnest wish of your sincere friend, Benjamin Hallowell Nelson is said to have been pleased with the gift, keeping it propped against the wall of his cabin for some time, behind the chair in which he sat for dinner, and taking it with him to his next command.

Hallowell faced a court-martial over this incident when he was returned to England after a short time as a prisoner of war, but he was honorably acquitted of any failure of duty.

[21] Hallowell was awarded the Neapolitan Order of Saint Ferdinand and Merit[22] for his actions during the siege of Corsica, an honour also presented to Nelson.

[25] In 1828, Sir Benjamin Hallowell succeeded to the estates of the Carew family of Beddington, Surrey, on the death of his cousin, who had herself inherited them from her brother-in-law.

His countenance was open, manly, and benevolent, with bright, clear grey eyes, which, if turned inquiringly upon you, seemed to read your most secret thoughts.

His mouth was pleasing and remarkably handsome, but indicative of decision and strength of character; and his thinly scattered hair, powdered, and tied in a cue [sic] after the old fashion, displayed, in all its breadth, his high and massive forehead, upon which unflinching probity and sterling good sense seemed to have taken their stand.Hallowell-Carew married Ann Inglefield, daughter of John Nicholson Inglefield.