HMS Barfleur was a 90-gun second-rate ship of the line of the Royal Navy, designed by Sir Thomas Slade on the lines of the 100-gun ship Royal William, and launched at Chatham Dockyard on 30 July 1768, at a cost of £49,222. In about 1780, she had another eight guns added to her quarterdeck, making her a 98-gun ship; she possessed a crew of approximately 750. Her design class sisters were the Prince George, Princess Royal, and Formidable. She was a ship of long service and many battles.