During September 1779, the four remaining vessels from a seven-strong squadron, which had departed from the anchorage at Groix off L’Orient in France on 14 August, nominally under the command of American Continental Navy captain John Paul Jones, voyaged from a brief stop off Ireland, round the north of Scotland, and down the east coast of Britain, creating havoc wherever possible.

On the evening of 22 September, Jones in Bonhomme Richard (an armed former French East India Company trading vessel he had reluctantly adapted for military use), accompanied by the little brigantine Vengeance under Captain Philippe Nicolas Ricot, had been off Spurn Head, hoping to catch a few prizes emerging from the Humber estuary, but he decided to head northward during the hours of darkness, and rendezvous with his frigates Alliance and Pallas, which had parted company from him further up the coast.

Jones's crew was called to quarters, but when daylight approached, about 5:30 am, and a chequered flag was hoisted on the mizzen mast, the mystery vessels finally identified themselves as the Alliance and Pallas.

[3] [4] Early in the afternoon, the reunited squadron sighted a brig in Bridlington Bay, so at about 3:30 pm, a small schooner, captured just the previous day, was sent with a 15-man boarding party.

There is a discrepancy at this point between Jones's official report and Bonhomme Richard’s log, but the reason for sending the schooner may have been not because the brig was in very shallow water, but because the main squadron was on its way to investigate a sighting of a ship further north near Flamborough Head.

At least two large vessels had been sighted in the distance, so the schooner was immediately recalled by firing a signal gun, and the entire squadron headed towards the potentially rich prizes.

[2] On 15 September, a convoy of more than 50 ships, which had been trading with ports in the Baltic, had set sail from a rendezvous off the Norwegian coast at the mouth of the Skagerrak channel to cross the North Sea.

[5] When the Yorkshire coast was sighted early on 23 September, just over 40 remained, mostly carrying iron or timber (often in the form of planks and masts for ships), bound for ports all around the southern half of the British Isles, from Hull round to Bristol, and Waterford in Ireland.

About 4 pm, with the whole convoy to his north, and the squadron of strangers clearly in sight to the south, Captain Richard Pearson of the Serapis signalled Countess of Scarborough to join him.

As the squadron caught up, the Royal Navy vessels made sure to position themselves so that the presumed enemy could not easily sail round them to reach the slower merchant ships.

[7] As the situation became clear, Alliance gradually slowed, allowing the rest of Jones's squadron to catch up (except for the little schooner carrying the boarding party, which could not sail fast enough).

[8] In order to prevent him from sailing right past and chasing the convoy, Captain Thomas Piercy of the Countess of Scarborough had to do the same, leaving Serapis alone against the remaining three American ships.

[4] Piercy, his ship relatively unharmed, and out of range of any of the four Americans, headed straight for the main battle, to see if he could help Serapis, but Jones's close-quarters policy meant that to intervene now would be madness.

Cottineau saw the potential danger (or responded to a request by Landais[4]) and quickly steered towards the Countess of Scarborough, so Piercy slowly retreated, sailing with the wind.

Serapis' jib-boom caught in the rigging of Bonhomme Richard's mizzen mast, and Jones immediately led his crew in attaching the two ships together as strongly as they could.

Making a virtue of necessity, Pearson’s crew fired broadsides straight into Bonhomme Richard's hull, tearing huge holes in its side, and doing terrible damage to the gun decks.

Two of these guns were loaded with anti-personnel grapeshot to help drive Pearson's men from the deck, but the third was used with solid bar-shot (see Naval Artillery page) aimed at Serapis' mainmast.

As the direction of shots was now predictable, Captain Landais could safely approach within firing range of Serapis, from the right direction- bow or stern rather than flank.

As much lethal shot hit Jones's men as Pearson’s, and metal also flew along Bonhomme Richard's gun deck, killing some of the remaining gunners and wrecking several gun-carriages.

[8] Jones himself recalled shouting something along the lines of "I have not yet thought of it, but I am determined to make you strike," at which point, presumably, the surrendering officers realised he was still very much alive and returned to their duties.

[7] By this time, the attempts to bring down Serapis' main mast had also borne some fruit (ironically, the only reason why it had not fallen down was because it was leaning on Bonhomme Richard's rigging).

Bonhomme Richard was clearly showing agreed lantern signals, but Landais stuck to his plan,[3] sailing round the "safe" sides of the locked ships to fire broadsides aimed, in his theory, at both bow and stern of Serapis.

In reality, Bonhomme Richard, yet again, was holed below the waterline and started settling so rapidly that the master-at-arms took it upon himself to release the hundred or so prisoners from previous captures, who had been held on the lower decks.

[10] A short time later, as Captain Pearson was boarding Bonhomme Richard to hand over his ceremonial sword, the mainmast of Serapis finally fell overboard, perhaps as a result of work to separate the two ships, dragging the damaged mizzen-top-mast with it.

[16] The combatants had been observed by thousands of onlookers, for on that clear night, with a near-full moon, the action could be seen from a long stretch of the high Yorkshire coastline, from Scarborough in the north to Flamborough Head itself in the south.

At 2 pm the next day, with the carpenter insisting that the ship could not be saved, Commodore Jones took the ex-captain and lieutenant of Serapis to safety, but returned early in the evening to check on progress.

The flotilla was slowly moving east-south-east away from the coast all this time,[17] and was not seen from land again after night fell (as Flamborough Head is about 400 feet (120 m) high, ships’ sails would be visible on a clear day up to 30 miles (48 km) away).

Jones wished to take his prizes to Dunkirk, but the French captains insisted on following the original orders from their government masters to head for the island of Texel in the neutral United Provinces (the Netherlands).

On 8 October, the British ambassador, Sir Joseph Yorke, wrote to the rulers of the United Provinces, claiming that under international law, Jones, not being accredited by a recognised state, was a rebel and a pirate.

That request was agreed to immediately, but it was over a fortnight later, during which repair work proceeded without any hindrance, when the Dutch replied that their neutrality meant they could not judge the legality of actions between foreigners on the open sea, but that would also apply to any attempt made by the British to retake their ships once they left port.