The concept of the '74' originated in France with the building of L'Invincible in 1744 and, once in service, she was immediately recognised as a revolution in naval design. When that same ship was captured by Admiral Anson in 1747, the Admiralty was presented with a unique opportunity to study her and it proved a seminal moment in the history of the Royal Navy. By the end of the eighteenth century, '74's' formed the backbone of both the Royal Navy and the navies of its traditional enemies and were viewed on all sides as the most useful and effective battleships of their day.
Mont Blanc was laid down in 1789, just as the French Revolution was starting, and launched two years later. Part of Admiral Villaret-Joyeuse's fleet sighted by Lord Howe on 28th May 1794, she fought in the skirmishes that day and the next but was then ordered home to escort the damaged 86-gun Indomptable back to port, thereby missing participation in the action known as the 'Glorious 1st of June'. In 1803, she sailed with Villeneuve's fleet to the West Indies and back as the wily French commander attempted to hoodwink Lord Nelson, and she was in action again on 22nd July 1805 in the indecisive encounter with Vice-Admiral Sir Robert Calder's squadron off Ferrol. At Trafalgar, under Capitaine Jean Noel de Lavillegris, she was part of Admiral Dumanoir's van squadron and, as such, played only a minor part in the battle before escaping away to the south-west when it became clear the day was lost. Having 'fled the field' at Trafalgar, she was amongst the surviving French ships hunted down and brought to action west of Rochefort by Admiral Sir Richard Strachan on 4th November . Hotly engaged by Strachan's ships on both sides, Mont Blanc took a tremendous battering before surrendering, after which it took immense efforts from both her own men as well as the British prize crew to prevent her foundering. Too damaged for further active service, she was converted into a prison hulk at Portsmouth and finally broken up in 1819.