Hopsonn was born in Shalfleet on the Isle of Wight, where he was baptised on 6 April 1643, the second son of Captain Anthony Hopson (d. 1667) and his wife Anne Kinge.

Samuel Smiles tells the tale thus in Self Help: He was working as a tailor's apprentice near Bonchurch, in the Isle of Wight, when the news flew through the village that a squadron of men-of-war was sailing off the island.

The boy was suddenly inflamed with the ambition to be a sailor; and springing into a boat, he rowed off to the squadron, gained the admiral's ship, and was accepted as a volunteer.

[4] However it happened, Hopsonn seems to have joined the navy by 1662,[5] and was mentioned as a "particular friend" of Samuel Pepys' brother-in-law, Balthazar St Michel, in 1666.

After serving initially on the coast of Ireland, his ship was part of the fleet led by George Legge to conduct the evacuation of Tangier.

The convoy was attacked and scattered by the French admiral Comte de Tourville at the Battle of Lagos, but no blame was attached to Hopsonn in the subsequent inquiry.

[1] In 1696 he gave up his commission in the Foot Guards, and in 1698 he was elected, thanks to the influence of Lord Cutts, to the rotten borough of Newtown on the Isle of Wight.

[5] He spent 1699 off the coasts of Ireland and France, with his flag aboard the Kent, in 1700 he went to the Baltic with Rooke to encourage Denmark to withdraw from the Great Northern War.

After a month of operations the attack came to nothing, but on the way home Rooke learned of the Spanish treasure fleet lying in Vigo Bay in Northern Spain.

"[8] On returning to England, Hopsonn was knighted by Queen Anne for his actions at Vigo Bay and retired from active service.

[10] The couple had eight children:[2] His nephew, erroneously supposed by some sources to have been his younger brother, Edward Hopson (1671–1728) also went into the navy and rose to the rank of vice-admiral of the white.