Thétis was a 40-gun Nymphe-class frigate frigate of the French Navy

French Navy

The French Navy, officially the Marine nationale and often called La Royale is the maritime arm of the French military. It includes a full range of fighting vessels, from patrol boats to a nuclear powered aircraft carrier and 10 nuclear-powered submarines, four of which are capable of launching...

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From 1790, she served in various diplomatic missions in the Indian Ocean, before returning for a refit in Brest in 1793. From 1795, she was shuttled from France to Guadeloupe. She took part in the Invisible Squadron

Allemand's expedition of 1805

Allemand's expedition of 1805, often referred to as the Escadre invisible in French sources, was an important French naval expedition during the Napoleonic Wars, which formed a major diversion to the ongoing Trafalgar campaign in the Atlantic Ocean...

 of Zacharie Allemand

Zacharie Allemand

Zacharie Jacques Théodore Allemand, was a French admiral.- Early career :Allemand was born to a captain of the East Indian Company. Orphaned at an early age, he started his sailing career at 12 as an apprentice on Superbe, an East Indiaman...

, before returning to Martinique along with the 16-gun brig Lynx.

The Chroniques de la Marine Française report that in 1807, she captured a 18-gun brig name Methly

She was captured off Lorient by HMS Amethyst

HMS Amethyst (1799)

HMS Amethyst was a Royal Navy 36-gun Penelope-class fifth-rate frigate, launched in 1799 at Deptford. Amethyst served in the French Revolutionary Wars and the Napoleonic Wars, capturing several prizes. She also participated in two boat actions and two ship actions that won her crew clasps to the...

 in the Action of 10 November 1808

Action of 10 November 1808

The Action of 10 November 1808 was a minor naval engagement of the Napoleonic Wars, in which a British frigate defeated and captured a French frigate in the Bay of Biscay...

, and brought in British service as HMS Brune.