When the French troops, led by Baron de Rullecourt, landed in the early morning at La Rocque in the parish of Grouville, they quickly moved on to St Helier, leaving behind a rearguard to protect their boats. Estimates of the number of French soldiers who set out from Chausey to attack Jersey, how many landed and how many took part in the battle in the Royal Square vary enormously. The upper end of the estimate of the total number of men de Rullecourt left France with is 2,000, and given that he is believed to have had good intelligence of the number of troops stationed in Jersey - well in excess of that number - it is doubtful that he would have left with fewer of his own men. But it is generally believed that about 100 men remained at La Rocque while a force of perhaps 700 headed for St Helier, indicating that perhaps more than half the invasion force failed to land before the tide ebbed on that winter morning.
The French landed unseen at Plat Rocque, because the closest guardhouse at La Rocque Point was either deserted or the guards were drunk. This guard was at the Guard House and Tower at Le Boulevard de La Rocque in Grouville Bay (La Rocque Point). The tower is La Rocque Tower (Grouville Bay No 1) which was one of the few coastal towers yet to have been completed, having been built in 1779. The Guard House was the St Saviour's guard house, variously known as Le Boulevard guard house, St Sampson's guard house (incorrectly, probably mistranscription of St Saviour's as it was built and manned by St Saviour, although the Sette Sampson is on the foreshore, at a distance, opposite), La Rocque guard house (guard house at La Rocque or at Le Boulevard de La Rocque).
Plat Rocque Tower, Grouville No 0, did not yet exist, but the guard and guard house were around the corner at La Rocque Tower.
Evidence at the Chef de Garde's court martial stated that "the Chef de Garde was intoxicated, and neglected to fix his sentinel on the battery, which so perfectly commands the shore that no such noise as the landing of troops could escape the ear of any man who was awake. He sent no tide patrols, which his orders strictly enjoined. He quitted guard himself before the day, and suffered his men to follow his example in disobedience of the orders which direct the night guards not to quit their posts till relieved an hour after it is light".
When the French troops arrived in the Royal Square, Captain Clement Hemery of the Militia, whose house overlooked the square, was disturbed by the noise and going to his window saw the French in the street. His house was surrounded, so, dressed in civilian clothes, escaped through his cellar, leaving by a grating into Morier Lane (now Halkett Place). He called at the house of Lieut-Governor Moyse Corbet, who told him to ride to warn Captain William Campbell of the 83rd Regiment, who was in the barracks at Fort Conway, Grouville. Hemery had scarcely left when the French surrounded the house.
On his way back from warning the posts and forts as far as Mont Orgueil, he was observed by a party of French soldiers and captured. He was placed under guard in one of the French flat-bottomed boats in shallow water at La Rocque, when his captors were fired upon by a group of militiamen. Clement proposed going to parley with them "to save unnecessary bloodshed", and when this ruse was accepted he went to report to Corbet, but finding his house surrounded he made his way to Gallows Hill and joined Major Peirson’s forces.
Major Peirson’s forces advanced into St Helier and after a short but fierce engagement the French surrendered. Hemery took part in the battle and is pictured in the painting by John Singleton Copley.
Another warning of the arrival of the French was given to Corbet by St Helier blacksmith John Laugée. He was then sent to alert Militia Colonel Messervy at his town house, where he supposedly found him writing by candle light. Laugée then rode to Grouville to alert Captain Campbell (who presumably already knew from Captain Hemery what was happening), and on to St Martin to warn the Rector, the Rev Francis Le Couteur, a member of the island's Defence committee.
Campbell sent Lieutenant William Nivon to St Helier to obtain orders from Corbet, but reports say that he was delayed six hours, having been captured by the French at one stage, and it is not clear whether he returned before Campbell eventually decided to attack the French rearguard at Platte Rocque.
After the Battle in the Royal Square, Corbet, back in charge, ordered Captain Robert Lumsdaine, with five companies of the 78th regiment and the 95th regiment, to march to La Rocque. When he arrived the French vessels were lying very near the rocks, awaiting events; but on seeing the troops, and receiving a few shot from them, they weighed anchor and set sail for France.
The exact sequence of subsequent events is very uncertain. Captain Lumsdaine apparently found Captain William Campbell already at La Rocque with five companies of the 83d regiment. He had marched there with all the men who could be spared from the fort; joined by Colonel Messervey, with the East regiment of militia, whom he met en route.
Some reports suggest that Campbell had received Corbet's earlier instructions for all troops to lay down their arms and was reluctant to attack the La Rocque rearguard, but there is no evidence for this. It appears more likely that he was just waiting for more information about what was happening in St Helier and for the return of Lieutenant Nivon. Whether the Rev Le Couteur's arrival convinced him that he should attack is uncertain, as is the exact disposition of the French troops at La Rocque.
One report suggests that the enemy had barricaded themselves up in the redoubt and the guardhouse at La Rocque and that Campbell decided to storm it with the grenadier company of the 83d regiment. To prevent the enemy from escaping, he divided the company into two equal parts, commanding one himself, and giving the other to Lieutenant James Robertson. They attacked the redoubt on opposite sides.
Robertson's party came under heavy fire from the enemy, which killed six, and wounded seven or eight men but the guard-house door was forced open and most of the enemy threw down their arms, after having 20 killed and as many wounded. At this instant, Captain Campbell, with his party, entered the redoubt, and joined in pursuing the fugitives, who fled to the rocks.
This seems an unlikely course of events because the guardhouse would only have had room for a fraction of the 100 French soldiers. But the open battle portrayed in the Ouless painting at the top of the page is even more fanciful.
Other reports show Campbell's force of about 400 to 500 men being joined by a Militia detachment. He is said to have sent Lieutenant Robertson ahead with 40 men who were joined by ten militiamen.
The article on the battle by Melvyn Green in the 1981 Annual Bulletin of La Société Jersiaise says that it is not known exactly where the battle took place. It could have been at the La Rocque guardhouse, but tradition places it at Platte Rocque, several hundred metres to the west where La Rocque Harbour has subsequently been constructed, as the French attempted to escape in their boats. However, other reports suggest that all the French vessels had long since retreated from the shore.
Green favours the guardhouse at La Rocque as the location of the battle, on the grounds that the French would have sought its shelter rather than remaining in open ground where they had landed that morning at Platte Rocque.
- "Lt Robertson acted with great courage, almost with rashness. With 50 men under his command, he had to attack a defending force of at least twice that number, possibly in an entrenched position and, we may assume, possessing the La Rocque battery guns. He could not have been aware of the poor condition of the French troops. Short of food and ammunition, weakened by the privations and hardships of the preceding week, mainly spent in small boats at sea, they were in no state to resist a determined assault.
- "Advancing close to the enemy, Robertson opened fire and attacked at once. The French replied, but their cannons refused to fire, and after a short, fierce engagement, the defenders broke, some running towards the rocks and the safety of the boats.
- "Though the engagement was short, the casualties, with so many men in so small an area, were heavy. At least a sixth of those involved in the action were killed: on the French side 20 men and an officer; of the force commanded by Lt Robertson, seven grenadiers.
- "In addition nine of his force were wounded, and among those seriously so was the militia officer, Lt Godfray. All was over before Capt Campbell could arrive with the main party."
The account continues by suggesting that the Rev Le Couteur's guns opened fire on a French vessel attempting to rescue enemy troops.
After the battle was over it is suggested that Lieutenant Snow of the Militia arrived with Corbet's command that the French should not be attacked, and Lieutenant Niven returned shortly after with a further signed copy of this order. All of this is supposed to have happened by 1 o'clock, at which time Campbell decided to march to St Helier, anticipating Corbet's wrath at having his order disobeyed.
The Rev Le Couteur, however, pledged his support for Campbell, saying that he had had no option but to attack the French, and because Corbet had been a prisoner, his order was not valid. Then another courier arrived with Major Francis Peirson's request for assistance. and a short time later, yet another with news that the Battle of Jersey was over and the French had been defeated.
In the event it was Moyse Corbet who faced a court martial for his actions on the day, and Campbell, Robertson and Le Couteur were counted with Peirson among the day's heroes.