The discipline in the French army under Massena had been greatly injured by its long inactivity. The only news he received as to Soult's movements was that he was near Badajoz; therefore, the first week in March he began his retreat, by sending off 10,000 sick and all his stores to Thomar. Then he began to fall back. Thick weather favoured him, and Ney assembled a large force near Leiria, as if to advance against the British position. Two other corps left Santarem, on the night of the fifth, and retired to Thomar. The rest of the army moved by other routes.

For four days Wellington, although discovering that a retreat was in progress, was unable to ascertain by which line Massena was really retiring. As soon as this point was cleared up, he ordered Beresford to concentrate near Abrantes; while he himself followed the line the main body of the French army seemed to be taking. It was soon found that they were concentrating at Pombal, with the apparent intention of crossing the Mondego at Coimbra; whereby they would have obtained a fresh and formidable position behind the Mondego, with the rich and untouched country between that river and the Douro, upon which they could have subsisted for a long time.

Therefore, calling back the troops that were already on the march to relieve Badajos, which had not yet surrendered, he advanced with all speed upon Pombal, his object being to force the French to take the line of retreat through Miranda for the frontier, and so to prevent him from crossing the Mondego.

Ney commanded the rear guard, and carried out the operation with the same mixture of vigour, valour, and prudence with which he, afterwards, performed the same duty to the French army on its retreat from Moscow. He fought at Pombal and at Redinha, and that so strenuously that, had it not been for Trant, Wilson, and other partisans who defended all the fords and bridges, Massena would have been able to have crossed the Mondego. Wellington however turned, one by one, the positions occupied by Ney; and Massena, believing that the force at Coimbra was far stronger than it really was, changed his plans and took up a position at Cazal Nova.

Here he left Ney and marched for Miranda but, although Ney covered the movement with admirable skill, disputing every ridge and post of vantage, the British pressed forward so hotly that Massena was obliged to destroy all his baggage and ammunition. Ney rashly remained on the east side of the river Cerra, in front of the village of Foz d'Aronce and, being attacked suddenly, was driven across the river with a loss of 500 men; many being drowned by missing the fords, and others crushed to death in the passage. However, Ney held the line of the river, blew up the bridge, and his division withdrew in good order.

Massena tarnished the reputation, gained by the manner in which he had drawn off his army from its dangerous position, by the ruthless spirit with which the operation was conducted; covering his retreat by burning every village through which he passed, and even ordering the town of Leiria to be destroyed, although altogether out of the line he was following.

After this fight the British pursuit slackened somewhat, for Wellington received the news of the surrender of Badajoz and, seeing that Portugal was thus open to invasion by Soult, on the south, despatched Cole's division to join that of Beresford; although this left him inferior in force to the army he was pursuing. The advance was retarded by the necessity of making bridges across the Cerra, which was now in flood, and the delay enabled Massena to fall back unmolested to Guarda; where he intended to halt, and then to move to Coria, whence he could have marched to the Tagus, effected a junction with Soult, and be in a position to advance again upon Lisbon, with a larger force than ever. He had, however, throughout been thwarted by the factious disobedience of his lieutenants Ney, Regnier, Brouet, Montbrun, and Junot; and this feeling now broke into open disobedience and, while Ney absolutely defied his authority, the others were so disobedient that fierce and angry personal altercations took place.

Massena removed Ney from his command. His own movements were, however, altogether disarranged by two British divisions, marching over the mountains by paths deemed altogether impassable for troops; which compelled him to abandon his intention of marching south, and to retire to Sabuga on the Coa. Here he was attacked. Regnier's corps, which covered the position, was beaten with heavy loss but, owing to the combinations--which would have cut Massena off from Ciudad Rodrigo--failing, from some of the columns going altogether astray in a thick fog, Massena gained that town with his army. He had lost in battle, from disease, or taken prisoners, 30,000 men since the day when, confident that he was going to drive Wellington to take refuge on board his ships, he had advanced from that town.

Even now he did not feel safe, though rejoined by a large number of convalescents; and, drawing rations for his troops from the stores of the citadel, he retired with the army to Salamanca. Having reorganized his force, procured fresh horses for his guns, and rested the troops for a few days; Massena advanced to cover Ciudad Rodrigo, and to raise the siege of Almeida--which Wellington had begun without loss of time--and, with upwards of 50,000 men, Massena attacked the British at Fuentes d'Onoro.