The French and Spanish not only wished to retrieve lost territory from Britain but needed to secure Gibraltar, which was a key link in Britain's control of the sea. The fortress was besieged for nearly four years by the full naval and military strengths of the enemy. When the Rock was first besieged, the garrison consisted of 5,382 troops; General Elliot was the Governor-General, and his determined handling of the defence inspired all the troops under him with the greatest confidence. All the defences were strengthened, and many of the infantry, including picked men from the 39th Regiment, assisted the artillery in serving the guns.
The combined Spanish and French fleets blockaded the Rock from the sea, while on the land side an enormous army was engaged in constructing forts, redoubts, entrenchments, and batteries from which to attack. General Elliot formed a corps of sharpshooters, the command of which was given to Lieutenant Burleigh, of the 39th Regiment, which rendered splendid service in keeping the enemy constantly engaged, and inflicting heavy losses.
As the winter of 1779 came down the garrison began to suffer from want of fresh provisions, which became very scarce and dear. Bread was almost impossible to get, and was not permitted to be issued except to the sick and children. Salt meat and biscuits, and not much of that, soon became the food of the troops, with an occasional issue of four ounces of rice as a full day's ration. Fuel was exhausted, and fires were only made with difficulty, the salt-encrusted timbers of old ships broken up in the harbour for the purpose. To the rigours of the siege was added a violent outbreak of scurvy among the devoted troops, due to the want of fresh vegetables and medicines. As the winter wore on, the scanty store of food grew so alarmingly low that the already meagre ration was reduced to just enough to keep life in the bodies of the men. But their morale remained high and the troops continued to take their turns at trench or battery, and endured the inclement weather and the shortage of food with fortitude.
Admiral Rodney, after defeating two enemy fleets at sea, reached Gibraltar in the following spring, bringing welcome reinforcements of 1,052 men and an abundance of stores. This greatly heartened the garrison, who, as soon as Rodney's fleet left, found the fortress as closely besieged as ever. The defence was stubbornly maintained against every attempt to capture it by assault, and by the end of the summer provisions again began to run out and scurvy to reappear. While shot and shell were unceasingly exchanged between the opposing forces, scurvy and starvation rations made steady inroads into the effective strength of the garrison, but there was no thought of surrender. Throughout the second winter the gallant garrison faced foes, elements, disease, and starvation, until in the April of 1781 another British fleet succeeded in reaching the harbour with stores and food.
The French and Spanish, finding it was impossible to starve the gallant garrison out, they resolved to make further desperate attacks by land and sea, and a large army and fleet was assembled to carry this out. The adjacent hills over the Spanish border became thronged with great crowds of spectators, among them the highest families in the land, assembled to see the fortress beaten to powder and 'the British flag trailed in the dust'. But the night before the grand attack was to have been launched, half the British garrison filed silently out of their defence works and made surprise sortie.
The whole body of the enemy infantry in the trenches were routed, their batteries set on fire, and cannon blown up and spiked, their entrenchments destroyed, and a very large number of the enemy killed or taken prisoners. Damage to the extent of two million pounds was done to the enemy's stores and equipment in that night's work, in which the 39th took a leading part. The loss to the British was less than one hundred. This reverse postponed the grand assault on the Rock for some time, but the siege was closely maintained. Eventually, the enemy launched their great attack; 200 heavy guns opened fire from floating batteries in the Bay and a further 400 guns on the land side, directed on the fortifications after weeks of preparatory artillery fire. But the garrison, replied with red-hot shot to set fire to and sink the enemy's floating batteries and warships in the Bay, and beating off many attempts to storm the fortress from the land side. In that great conflict, the British destroyed nearly all the enemy fleet, with over 5,000 men on board.
The siege was continued for some months longer, but in the spring of 1783 the enemy retired disheartened and defeated, leaving the British garrison victorious, after three years and seven months' conflict. The garrison sustained a loss of 1,231 men, and expended 8,000 barrels of gunpowder. The 39th, in common with the other regiments engaged in the defence, was given the badge of the Castle of Gibraltar with the motto 'Montis Insignia Calpe', in commemoration of the gallant part it took in the 'Great Siege'.
Click here for a brief biography of Sir George Nugent who fought with the 39th Regiment of Foot at the Great Siege of Gibralta.