Admiral Sir John Colpoys, GCB (c. 1742 – 4 April 1821) was a Royal Navy officer who served in three wars but is most notable for being one of the catalysts of the Spithead Mutiny in 1797 after ordering his marines to fire on a deputation of mutinous sailors.

In 1778, shortly after leaving the frigate, Colpoys was called to an Admiralty court as a judge in the court-martial of Sir Hugh Palliser in the acrimonious aftermath of the First Battle of Ushant.

As instructed, the court found Palliser innocent of any wrongdoing and Colpoys returned to sea as commander of HMS Orpheus on the North American Station.

[1] In Orpheus, Colpoys achieved his one victory at sea when, in company with HMS Roebuck, he successfully ran down and captured the small frigate USS Confederacy in 1781.

With the renewal of conflict with France in 1793 in the French Revolutionary Wars, Colpoys was recalled to active service as a squadron commander under Alan Gardner in the Channel and subsequently the West Indies.

Rather than pursue the French, Colpoys took his ships into Plymouth for a refit while the main body of the Channel Fleet hunted for the invasion force.

Disaffected sailors in the Channel Fleet at Spithead went on strike, demanding a number of concessions before they would return to offensive operations.

[1] Colpoys was removed from active service at this time, although this may not have been a condemnation of his actions: he had already requested to be relieved before the mutiny due to his deteriorating health.

[1] No longer serving at sea, Colpoys began to recover his health and was rewarded for his long service in 1798 with appointment as a Knight Companion of the Order of the Bath.