The Austrians formed three corps, one (Quasdanovich, 18,000 men) marching round the west side of the Lake of Garda on Gavardo, Salo and the Brescia road, the second (under Wurmser, about 30,000) moving directly down the Adige, and the third (Davidovich, 6000) making a détour by the Brenta valley and heading for Verona by Vicenza.
On the 29th Quasdanovich attacked Sauret at Salo, drove him towards Desenzano, and pushed on to Gavardo and thence into Brescia. Wurmser expelled Masséna’s advanced guard from La Corona, and captured in succession the Monte Baldo and Rivoli posts. The Brenta column approached Verona with little or no fighting. News of this column led Napoleon early in the day to close up Despinoy, Masséna and Kilmaine at Castelnuovo, and to order Augereau from Legnago to advance on Montebello (19 m. east of Verona) against Davidovich’s left rear. But after these orders had been despatched came the news of Sauret’s defeat, and this moment was one of the most anxious in Napoleon’s career. He could not make up his mind to give up the siege of Mantua, but he hurried Augereau back to the Mincio, and sent order after order to the officers on the lines of communication to send all convoys by the Cremona instead of by the Brescia road. More, he had the baggage, the treasure and the sick set in motion at once for Marcaria, and wrote to Sérurier a despatch which included the words “perhaps we shall recover ourselves ... but I must take serious measures for a retreat.” On the 30th he wrote: “The enemy have broken through our line in three places ... Sauret has evacuated Salo ... and the enemy has captured Brescia. You see that our communications with Milan and Verona are cut.” The reports that came to him during the morning of the 30th enabled him to place the main body of the enemy opposite Masséna, and this, without in the least alleviating the gravity of the situation, helped to make his course less doubtful. Augereau was ordered to hold the line of the Molinella, in case Davidovich’s attack, the least-known factor, should after all prove to be serious; Masséna to reconnoitre a road from Peschiera through Castiglione towards Orzinovi, and to stand fast at Castelnuovo opposite Wurmser as long as he could. Sauret and Despinoy were concentrated at Desenzano with orders on the 31st to clear the main line of retreat and to recapture Brescia. The Austrian movements were merely the continuation of those of the 29th. Quasdanovich wheeled inwards, his right finally resting on Montechiaro and his left on Salo. Wurmser drove back Masséna to the west side of the Mincio. Davidovich made a slight advance.
In the late evening Bonaparte held a council of war at Roverbella. The proceedings of this council are unknown, but it at any rate enabled Napoleon to see clearly and to act. Hitherto he had been covering the siege of Mantua with Relief of Mantua. various detachments, the defeat of any one of which might be fatal to the enterprise. Thus, when he had lost his main line of retreat, he could assemble no more than 8000 men at Desenzano to win it back. Now, however, he made up his mind that the siege could not be continued, and bitter as the decision must have been, it gave him freedom. At this moment of crisis the instincts of the great captain came into play, and showed the way to a victory that would more than counterbalance the now inevitable failure. Sérurier was ordered to spike the 140 siege guns that had been so welcome a few days before, and, after sending part of his force to Augereau, to establish himself with the rest at Marcaria on the Cremona road. The field forces were to be used on interior lines. On the 31st Sauret, Despinoy, Augereau and Kilmaine advanced westward against Quasdanovich. The first two found the Austrians at Salo and Lonato and drove them back, while with Augereau and the cavalry Bonaparte himself made a forced march on Brescia, never halting night or day till he reached the town and recovered his depots. Meantime Sérurier had retired (night of July 31), Masséna had gradually drawn in towards Lonato, and Wurmser’s advanced guard triumphantly entered the fortress (August 1).
The Austrian general now formed the plan of crushing Bonaparte between Quasdanovich and his own main body. But meantime Quasdanovich had evacuated Brescia under the threat of Bonaparte’s advance and was now fighting a long irregular action with Despinoy and Sauret about Gavardo and Salo, and Bonaparte, having missed his expected target, had brought Augereau by another severe march back to Montechiaro on the Chiese. Masséna was now assembled between Lonato and Ponte San Marco, and Sérurier was retiring quietly on Marcaria. Wurmser’s main body, weakened by the detachment sent to Mantua, crossed the Mincio about Valeggio and Goito on the 2nd, and penetrated as far as Castiglione, whence Masséna’s rearguard was expelled. But a renewed advance of Quasdanovich, ordered by Wurmser, which drove Sauret and Despinoy Lonato and Castiglione. back on Brescia and Lonato, in the end only placed a strong detachment of the Austrians within striking distance of Masséna, who on the 3rd attacked it, front to front, and by sheer fighting destroyed it, while at the same time Augereau recaptured Castiglione from Wurmser. On the 4th Sauret and Despinoy pressed back Quasdanovich beyond Salo and Gavardo. One of the Austrian columns, finding itself isolated and unable to retreat with the others, turned back to break its way through to Wurmser, and was annihilated by Masséna in the neighbourhood of Lonato. On this day Augereau fought his way towards Solferino, and Wurmser, thinking rightly or wrongly that he could not now retire to the Mincio without a battle, drew up his whole force, close on 30,000 men, in the plain between Solferino and Medole. The finale may be described in very few words. Bonaparte, convinced that no more was to be feared from Quasdanovich, and seeing that Wurmser meant to fight, called in Despinoy’s division to the main body and sent orders to Sérurier, then far distant on the Cremona road, to march against the left flank of the Austrians. On the 5th the battle of Castiglione was fought. Closely contested in the first hours of the frontal attack till Sérurier’s arrival decided the day, it ended in the retreat of the Austrians over the Mincio and into Tirol whence they had come.
Thus the new way had failed to keep back Wurmser, and the old had failed to crush Napoleon. Each was the result of its own conditions. In former wars a commander threatened as Napoleon was, would have fallen back at once to the Adda, abandoning the siege in such good time that he would have been able to bring off his siege artillery. Instead of this Bonaparte hesitated long enough to lose it, which, according to accepted canons was a waste, and held his ground, which was, by the same rules, sheer madness. But Revolutionary discipline was not firm enough to stand a retreat. Once it turned back, the army would have streamed away to Milan and perhaps to the Alps (cf. 1799), and the only alternative to complete dissolution therefore was fighting.
As to the manner of this fighting, even the principle of “relative superiority” failed him so long as he was endeavouring to cover the siege and again when his chief care was to protect his new line of retreat and to clear his old. In this period, viz. up to his return from Brescia on the 2nd of August, the only “mass” he collected delivered a blow in the air, while the covering detachments had to fight hard for bare existence. Once released from its trammels, the Napoleonic principle had fair play. He stood between Wurmser and Quasdanovich, ready to fight either or both. The latter was crushed, thanks to local superiority and the resolute leading of Masséna, but at Castiglione Wurmser actually outnumbered his opponent till the last of Napoleon’s precautionary dispositions had been given up, and Sérurier brought back from the “alternative line of retreat” to the battlefield. The moral is, again, that it was not the mere fact of being on interior lines that gave Napoleon the victory, but his “tact,” his fine appreciation of the chances in his favour, measured in terms of time, space, attacking force and containing power. All these factors were greatly influenced by the ground, which favoured the swarms and columns of the French and deprived the brilliant Austrian cavalry of its power to act. But of far greater importance was the mobility that Napoleon’s personal force imparted to the French. Napoleon himself rode five horses to death in three days, and Augereau’s division marched from Roverbella to Brescia and back to Montechiaro, a total distance of nearly 50 m., in about thirty-six hours. This indeed was the foundation of his “relative superiority,” for every hour saved in the time of marching meant more freedom to destroy one corps before the rest could overwhelm the covering detachments and come to its assistance.
Wurmser’s plan for the relief of Mantua, suited to its purpose, succeeded. But when he made his objective the French field army, he had to take his own army as he found it, disposed for an altogether different purpose. A properly, combined attack of convergent columns framed ab initio by a good staff officer, such as Mack, might indeed have given good results. But the success of such a plan depends principally on the assailant’s original possession of the initiative, and not on the chances of his being able to win it over to his own side when operations, as here, are already in progress. When the time came to improvise such a plan, the initiative had passed over to Napoleon, and the plan was foredoomed.
By the end of the second week in August the blockade of Mantua had been resumed, without siege guns. But still under the impression of a great victory gained, Bonaparte was planning a long forward stride. He thought that by advancing past Mantua directly on Trieste and thence onwards to the Semmering he could impose a peace on the emperor. The Directory, however, which had by now focussed its attention on the German campaign, ordered him to pass through Tirol and to co-operate with Moreau, and this plan, Bonaparte, though protesting against an Alpine venture being made so late in the year, prepared to execute, drawing in reinforcements and collecting great quantities of supplies in boats on the Adige and Lake Garda. Wurmser was thought to have posted his main body near Trent, and to have detached one division to Bassano “to cover Trieste.” The French advanced northward on the 2nd, in three disconnected columns (precisely as Wurmser had done in the reverse direction at the end of July)—Masséna (13,000) from Rivoli to Ala, Augereau (9000) from Verona by hill roads, keeping on his right rear, Vaubois (11,000) round the Lake of Garda by Riva and Torbole. Sahuguet’s division (8000) remained before Mantua. The French divisions successfully combined and drove the enemy before them to Trent.
There, however, they missed their target. Wurmser had already drawn over the bulk of his army (22,000) into the Val Sugana, whence, with the Bassano division as his advanced guard, he intended once more to relieve Mantua, while Davidovich with 13,000 (excluding detachments) was to hold Tirol against any attempt of Bonaparte to join forces with Moreau.
Thus Austria was preparing to hazard a second (as in the event she hazarded a third and a fourth) highly trained and expensive professional army in the struggle for the preservation of a fortress, and we must conclude that there were weighty reasons which actuated so notoriously cautious a body as the Council of War in making this unconditional venture. While Mantua stood, Napoleon, for all his energy and sanguineness, could not press forward into Friuli and Carniola, and immunity from a Republican visitation was above all else important for the Vienna statesmen, governing as they did more or less discontented and heterogeneous populations that had not felt the pressure of war for a century and more. The Austrians, so far as is known, desired no more than to hold their own. They no longer possessed the superiority of moral that guarantees victory to one side when both are materially equal. There was therefore nothing to be gained, commensurate with the risk involved, by fighting a battle in the open field. In Italien siegt nicht die Kavallerie was an old saying in the Austrian army, and therefore the Austrians could not hope to win a victory of the first magnitude. The only practicable alternative was to strengthen Mantua as opportunities offered themselves, and to prolong the passive resistance as much as possible. Napoleon’s own practice in providing for secondary theatres of war was to economize forces and to delay a decision, and the fault of the Austrians, viewed from a purely military standpoint, was that they squandered, instead of economizing, their forces to gain time. If we neglect pure theory, and regard strategy as the handmaiden of statesmanship—which fundamentally it is—we cannot condemn the Vienna authorities unless it be first proved that they grossly exaggerated the possible results of Bonaparte’s threatened irruption. And if their capacity for judging the political situation be admitted, it naturally follows that their object was to preserve Mantua at all costs—which object Wurmser, though invariably defeated in action, did in fact accomplish.