The loss of twelve officers and seventy-two men (killed or wounded), in the fighting of the 31st August, reduced the strength of the 51st woefully, and it was one of the regiments which could least afford such a depletion, since it was in the unfortunate situation of having no second battalion in England upon which to fall back for reinforcements of officers and men. Most regiments in the field had a second battalion at home, ready to make good the casualties in the foreign battalion as they occurred, but the fate of the 51st had been against its ever having been able to recruit a second battalion. The 68th, also, with which the 51st had been brigaded for the greater part of the war, was suffering from the same cause, and so reduced in numbers were the two regiments that it became a great question what to do with them. The regiments themselves were for linking up and forming themselves into what was termed a "provisional battalion," and Wellington agreed to the proposal; but the authorities at home, refusing to sanction anything of the kind, informed Wellington that, if he deemed it necessary, he could send the regiments home to recruit up to strength. But the Commander-in-Chief had no intention of parting with any of his tried soldiers, and he preferred weak battalions of veterans to full ones of recruits, so the 51st and 68th remained with Inglis's brigade of the 7th Division, to fight the war to a finish.
After the fall of San Sebastian, the 51st recrossed to the right bank of the Bidassoa and occupied its former position near Santa Barbara, facing Vera. Here it remained throughout the month of September, and early in October moved to Echallar, to await the development of Wellington's plans. Major Rice, who had been kept in England after the expiration of his sick leave, because the authorities thought that Wellington would send the regiment home, now rejoined, in the best of health and spirits, though disappointed at having missed the three months' fighting in which his regiment had taken part. He saw, however, that he was still in time to take his share of plenty of rough work; and so it proved.
Wellington, having driven the French out of northern Spain into the Pyrenees, at first had no intention of following them into France, his reasons being that Napoleon might at any moment send reinforcements to Soult, and that a French army (under Suchet) was still in possession of the Mediterranean province of Catalonia, in eastern Spain. With Suchet in his rear, his position was insecure; and if large reinforcements were despatched to Soult, the allied army might fare badly, although the proximity of the sea-base rendered disaster impossible. When, therefore, San Sebastian fell, Wellington inclined to transfer the war to Catalonia, but political pressure from home and the news of Napoleon's misfortunes in Germany combined to cause him to change his plans, when, as Napier says, he "matured an offensive movement as daring as any undertaken during the whole war"—in short, an assault on Soult's whole line of fortifications in the Pyrenees, and the invasion of France.
Between the opposing armies the Bidassoa flowed from Vera to the sea; but to the north and north-east of Vera there was no such well-marked dividing line—only the labyrinth of rocky spurs and ravines which seamed the mountain-slopes. Wellington's plan was to advance simultaneously on the right and on the left, the troops on the right storming Soult's fortified posts among the mountains, while those on the left forced the passage of the Lower Bidassoa. These operations were to have commenced ill the middle of September, but, owing to faulty arrangements in the matter of pontoons and subsequently to bad weather, they were deferred until the 6th October. That night everything was got ready, and at daybreak next morning Wellington's carefully laid plans were set going, their extraordinary boldness altogether deceiving Soult.
Under the protection of a heavy cannonade from San Marcial and the neighbourhood, the divisions on the left forded the Lower Bidassoa at several points almost before the French had fired a shot, and, turning the enemy out of his positions, crossed the frontier into France. At the same time, the Light Division advancing on Vera, and thence up the mountain-slopes, carried position after position with astounding impetuosity; while, farther away on the right, the 7th Division and others guarded the Echallar pass and various roads and tracks through the mountains. Desultory fighting went on upon the crests of the Pyrenees during the next two days, after which Wellington called a halt, and from his headquarters at Vera reorganised the commands of his army. Hill was given the right, from Roncesvalles to the Bastan; Beresford the centre, which included Echallar, where the 7th Division was posted; and Hope the left, from the Mandale mountain to the sea. Tents were brought up, and the troops encamped on their several positions, eagerly awaiting the order to move forward; but Wellington had not yet decided finally whether to invade France or to move back into Spain and carry the war into Catalonia. A month was thus spent, in the most inclement weather, on the summits of the bleak Pyrenees, and the allied army suffered great hardships, some of the posts being at times snowed up and cut off from provisions. Fortunately they were provided with tents—though they were a cold comfort; nevertheless, the shelter which they afforded was certainly preferable to bivouacs among the rocks.
Prior to the opening of the campaign of 1813, regiments had been unacquainted with the luxury of canvas, and it is wonderful how they managed to exist for so many years in such variations of climate. Whenever possible, the troops were billeted in the towns, villages, and farms; but when actually in the field the bivouac was resorted to, and as time went on the old soldiers became adepts at making themselves comfortable, in shelters formed of boughs of trees, or even in hastily constructed huts, when halting in the more wooded parts of the country. In 1812, tents were improvised out of blankets, two of which were fastened together by tapes sewn on to the sides, and then stretched over a pole supported by the arm piles; but these provided shelter for only four men, who, moreover, had but two blankets among them in which to sleep. The whole matter was one of transport, and Wellington had always refused to allow the movements of his army to be hampered by excessive baggage. By this time, however, the medical officers had learnt by experience that much of the sickness of the army was attributable to exposure, and the authorities at length sanctioned the issue of four tents per company, three for the men and one for the officers, but their carriage was not to entail any increase in the number of transport animals. Hitherto the company mules carried nothing except the heavy iron camp-kettles, or cauldrons, but now these were exchanged for lighter ones of tin, which the men (six to a kettle) took it in turn to carry on their knapsacks, while the mules carried the tents.
Meanwhile, Soult had taken advantage of the inaction of his foe, and had caused to be thrown up a complete chain of entrenchments, some thirty miles long, covering St Jean de Luz on his right, and extending along the course of the Nivelle to its upper waters, whence the left of his line stretched eastward to the river Nive. The centre was guarded by outworks, erected about the Smaller Rhune and Sarre, to the east of the Greater Rhune; and so strong was this vast line that the most careful reconnaissances could discover scarcely a single weak spot in it.
At length Wellington made up his mind to move on into France, for he had now learned that Suchet would not co-operate with Soult, and he had learned also that Napoleon had met with successes in Germany. The time, therefore, was opportune to attack Soult, and to delay might result in his opponent receiving reinforcements from Napoleon. The British commander arrived at this decision early in November, and on the 9th issued his orders. His plan was to strike at the French centre, cross the Nivelle at the bridge of Amotz, and attempt to divide Soult's force. Before any general advance could be made, however, it was necessary to clear the foreground by capturing the outworks in the Pyrenees, and the Light Division, still in position about the Greater Rhune, facing the strongly fortified Smaller Rhune, not a mile distant, was ordered to push forward on the morrow. This the regiments of the famous division did in the most gallant manner, thus opening what was known as the battle of the Nivelle, and sweeping the Frenchmen from their fortified posts at the point of the bayonet.
The strength of the enemy's right determined Wellington to make no immediate advance on that side, but to bring round Hill's and Beresford's divisions in a species of gigantic wheel, so as to cross the Nivelle above and below the bridge of Amotz, and cut Soult's army in two. While, therefore, the Light Division was fighting its way through the enemy's advanced works, the 4th and 7th Divisions were sent against the forts of San Barbe and Grenada. It was a day of grand work, but we can do no more than follow the fortunes of the 51st, in Inglis's brigade of the 7th Division.
By a stroke of luck for Major Sam Rice, Colonel Mitchell had been placed on the sick list at Echallar, and the command of the regiment devolved on the major, who soon showed that he was equal to the responsibility. From the mouth of the Echallar pass, the 7th Division advanced rapidly on the Grenada fort, which covered the village of Sarre, while the 4th Division moved against the neighbouring fort of San Barbe, the regiments carrying scaling-ladders, wherewith, if necessary, to storm the works. Such aids, however, were not needed, for the defenders, powerless to withstand the fire of the eighteen British guns which accompanied the attack, fled from the forts, and though they stood for a while at Sarre, they soon broke before the determined onslaught of the pursuers. The victorious divisions, as they forged ahead, presently found themselves confronted by two redoubts, Louis XIV. and Harastaguia. The former was immediately stormed and carried at the point of the bayonet, and attention was then paid to the latter, in front of which the 31st French Regiment had been placed as a covering force. Upon this unfortunate regiment the 7th Division fell forthwith, breaking it and putting it to the rout, and driving the garrison from the redoubt—even to the banks of the Nivelle.