Monarca was a 68-gun ship of the line of the Spanish Navy, launched in 1756. She fought in the Battle of Cape St Vincent in 1780, in which she was captured by the Royal Navy and subsequently commissioned as the third rate HMS Monarca. She came under the command of Captain John Gell who was under the orders of Sir Samuel Hood to go to the West Indies. However she was dismasted in a storm and obliged to return to Britain for refitting. She fought at the Battle of Cuddalore in 1783. She was sold out of the navy in 1791.