The Battle of Bicocca, 27 April 1522

Whenever the Italian Wars erupted anew, it was invariably at the initiative of the vainglorious and untrustworthy French Valois monarchy.

By his victory at Marignano in 1515, King Francis I (1515-1547) had gained possession of the Duchy of Milan, and, by virtue of his alliance with the Republic of Venice, was dominant in northern Italy.

With this he was never content. He continued to uphold a spurious claim to the Kingdom of Naples, and to envisage a French imperium over the entire Italian peninsula, in pursuit of which he was ever-prepared to renew the war when his great rival, Emperor Charles V (1519-1556), the ruler of Germany, Spain, and the Netherlands, was distracted elsewhere.

So it was in 1521. Charles faced a widespread popular revolt in Spain, which would take three years to suppress, and opposition in Germany, where an old enemy had renewed an alliance with the French and was making trouble on the Belgian border. Francis intervened in support of both, reigniting the Valois-Habsburg war for hegemony in Europe, and northern Italy again became the main cockpit of the conflict.

The initiative, though, was taken by the Imperialists. The old Italian condottiere Prosper Colonna succeeded in passing an army from the south through the politico-strategic barrier of the Franco-Venetian alliance and united it with Imperialist forces coming through the Alps from the north. Then, in collusion with the anti-French faction in Milan, he launched a surprise attack on the city. His forces swarmed in and took full possession, the hapless French marshal Odet de Foix, Vicomte de Lautrec, retreating with the wreck of his army to Cremona.

A French counter-strike the following year (1522) was inevitable. Francis hired 16,000 Swiss and 3,000 Italian condottieri of the ‘Black Bands’ (arquebusiers and light horse), dispatched some units of French gendarmerie (heavy cavalry) and infantry from home, and called on the Venetians to join their best troops to Lautrec’s muster for the new campaigning season.

The Bicocca campaign

Colonna was now outnumbered and Imperialist-held towns in north-western Italy were imperilled, notably Pavia, towards which Lautrec directed his forces with the deliberate intention of provoking the Imperialists to risk a pitched battle in the open to protect it, when, of course, he hoped to smash them with his superior army.

Colonna’s response was to fortify himself at the site of the Monastery of Certosa, which lay on the Pavia road about ten miles outside Milan, and thus to challenge Lautrec to fight him on ground of his choosing. The Frenchman was a cautious commander whose inclination was to refuse the challenge and instead manoeuvre in an attempt to dislodge the Imperialists from their improvised fortress. But it was not to be. And for a peculiarly Renaissance reason.

Lautrec’s Swiss mercenaries went on strike. They had not been paid and were going home unless there was an immediate attack on the Imperialist army; they were not interested in a prolonged campaign of manoeuvre.

The French marshal’s situation was invidious: either he accepted battle in the circumstances proferred or he lost the bulk of his heavy foot. He chose the former. The only saving grace was that the Swiss undertook to carry the main burden of battle: a frontal assault by pike phalanxes on the Imperialist line.

The Park of Bicocca

As it happened, Colonna had shifted his position, probably worried that Lautrec might manoeuvre so as to cut Colonna’s communications with his main base at Milan. He had located an equally strong position only four miles from Milan at the Park of Bicocca – a position that covered Milan yet still precluded a French advance down the Pavia road (lest the army be taken in flank attack while in column of route).

The Park of Bicocca comprised the walled ornamental garden of a local manor house. The garden itself and the surrounding fields were dissected by numerous irrigation ditches. The left flank was covered by a wall with marshy ground beyond, the right also by a wall and a notably deep-cut wet ditch that ran parallel with the Milan road. The front, facing north, 600 yards in length, was covered by a third enclosure wall with a sunken road along the outside. Here, Colonna deepened the hollow, used the upcast to create a rampart, and also built a series of artillery redoubts.

On the day of the battle, he deployed his Spanish arquebusiers four-deep along the rampart (enabling rolling fire), with blocs of Spanish and German pikemen in support behind them. His cavalry were held in reserve, deployed behind the foot towards the back of the park, their rear covered by the wall and ditch forming the southern side of the enclosure.

One potential point of weakness was a bridge across the eastern ditch in the right rear of the Imperialist position. A clear possibility was that French cavalry might pass down the Milan road, cross the bridge, and take the Imperialists in the rear while their foot assaulted the front. To guard against this, Colonna summoned Duke Francesco Sforza, the newly restored ruler of Milan, to bring his personal retinue and the city militia to hold the bridge.

The Swiss assault

After Colonna’s pickets had been driven in by Giovanni de’ Medici’s Black Bands, the Swiss immediately advanced to the assault in two massive pike blocs of 4,000 men each. Lautrec followed with the second line, comprising the rest of the Swiss, the French infantry, and the bulk of the gendarmerie. The Venetians – second-class troops – formed a third reserve line in the right rear. Marshal Lautrec’s brother, Lescun, was dispatched with a substantial cavalry force on a flank march around the Imperialist right, with the intention of passing the bridge giving access to the enemy rear.

The Swiss of the first division were ostensibly under the command of a French nobleman, the Sieur de Montmorency, who advised them to halt beyond artillery range, to give the French guns time to be brought forward to batter the defences before the infantry assault went in. He was ignored. Here was another weakness of mercenaries: they might do their own thing, even in the crisis of battle.

The ground in front of the sunken road was flat and open, and Colonna’s gunners had marked out the distances. The pike blocs, formed many ranks deep, were the densest of targets. The execution was murderous. It was later estimated that a thousand Swiss had fallen, one in eight, before they reached the sunken road.

This was only the beginning. The sunken road had become a massive obstacle. The height from the bottom of the hollow to the top of the rampart was roughly equivalent to that of a pike. The sides were near perpendicular and smooth-faced. The front ranks of Swiss were brought to a halt and the rear ranks concertinaed into them.

The effective range of the arquebus was only about 25 yards, but here the range was shorter still. Four successive volleys were discharged as the waiting lines of arquebusiers took their turn to step forward, discharge, and fall back to reload. The canton standards at the head of the two pike blocs all went down, along with the first three or four ranks of men. Meantime, the Imperialist gunners – their redoubts projecting forwards to allow enfilade – fired round after round into the struggling mass beneath them.

Even so, it was not quite over. Climbing over the bodies of the fallen, some Swiss clambered up the rampart and engaged the defenders hand-to-hand. But their formations, shattered by fire, were in no state to face the waiting Spanish and German pikemen as they advanced through the arquebusiers to repel the assault.

After half an hour of increasingly desperate attempts to break into the Imperialist position, the Swiss retired, slowly, grudgingly, in good order, leaving some 2,000 of their fallen comrades in the sunken road.

The flank attack

At the same time, Lescun was leading his 400 gendarmes on their flanking movement. They charged the troops guarding the bridge over the wet ditch, and forced their way into the Imperialist camp south of the park. This caused panic and frantic appeals for support.

In other circumstances, this might have been a serious matter, but in fact Lescun’s force was too heavily outnumbered to have any real impact. Colonna dispatched a sizeable cavalry force from the rear of his line in the park to check the French gendarmes, while the Duke of Milan – who seems to have been somewhat negligent in his defence of the bridge – advanced his 400 horse and 6,000 foot to block Lescun’s escape-route.

In the event, a small French force detached to hold the bridge held up the Milanese long enough to enable Lescun’s main body to get back over the bridge. The whole thing had been in the manner of a cavalry raid – alarming while it lasted, but lacking the weight to inflict serious damage. On the other hand, had the infantry assault on the sunken road succeeded, Lescun’s force would have been in prime position to exploit an Imperialist rout.

The French withdrawal

Montmorency’s first division of Swiss pikemen had been defeated. Lescun’s gendarmes had been forced to retreat. But the bulk of the French army had not yet been engaged. Both high commands were now in a quandary.

The French might renew the attack with their second and third divisions. They might combine a second frontal assault to pin the defenders with an attempt to work around the flanks; though the terrain was difficult, it was no more so than the sunken road.

The cautious Lautrec may have decided that the enemy position was too strong to be forced. Colonna’s army was only marginally smaller than his own, and the Imperialist commander had demonstrated exceptional military skill in both manoeuvre and defence. In the event, the Swiss again forced a decision, announcing their immediate departure. Without them, Lautrec was too weak in infantry to contemplate a second assault.

Matters might have been different had Colonna decided to leave his fortifications and mount a counter-attack. Some Imperialist troops – arquebusiers and light horse – had in fact followed the retreating Swiss. They were stopped by Giovanni de’ Medici’s Black Bands, sent forwards by Lautrec to cover the withdrawal of the Swiss and ensure the guns were got away.

The more aggressive of Colonna’s subordinates urged a general assault on an enemy assumed to be demoralised. He refused, on the grounds that the great bulk of the French army – horse and foot – was intact, and because he expected Lautrec’s army to break up of its own accord and be forced to retreat. He was, of course, proved correct.

Assessment

Not for the first time, unsupported Swiss pike blocs had suffered a crushing defeat, the first division of 8,000 men committed to the main assault at Bicocca taking 25% casualties. Without fire support – cannon to blast gaps in the defences, arquebusiers to give close-range support – pikemen could not overwhelm an entrenched line such as they confronted at Bicocca.

This time, the lesson was well-learnt. Never again did the Swiss advance with their accustomed aggression and confidence. As one contemporary chronicler wrote, reflecting on the effective end of a 200-year-old tradition: ‘They went back to their mountains diminished in numbers, but much more diminished in audacity; for it is certain that the losses they suffered at Bicocca so affected them that in their coming years they no longer displayed their wonted vigour.’

This was noticed by others in years to come. At Pavia, for example, in February 1525, their assault miscarried entirely, as Charles Oman describes: ‘Harassed by the volleys of the arquebusiers… they came on slowly, hardly got to “push of pike”, and finally went off to their left and retreated en masse on the Milan road, with their commander Diesback at their head.’ None of the chroniclers either on the French or the Imperialist side has a good word to say for their conduct.

No less clear at Bicocca was the importance of obstacles – whether existing features or improvised fortifications – in infantry warfare. These were a protection against enemy shot and against cavalry attack, but in particular they afforded protection to otherwise highly vulnerable arquebusiers, and gave them opportunity to deliver a sufficient weight of shot to shatter enemy pike formations.

There were essentially three ways to deploy arquebusiers: as skirmishers, operating as light infantry ahead of the main line or on the flanks, ideally in close terrain (amid ditches, hedgerows, enclosures, woods, and so on); in loose but deep formation alongside their own pikemen, where they could deliver rolling fire and then fall back on the protection of the pikes; or behind linear defence-works sufficiently strong to halt the impetus of any enemy assault and give them time to destroy it with fire.

Worthy of note, too, is the form of Colonna’s entrenched camp, which, unlike that of the Imperialists at Ravenna in 1512, had the depth to ensure that the rear ranks were out of range of enemy artillery. In the event, the impetuosity of the Swiss afforded the excellent French gunners no time to do their work; but Colonna could not have known this in advance, and, like so much else about Bicocca, it is to his credit that he formed a position designed to minimise the danger.

Finally, Bicocca demonstrated the supreme importance of combined-arms tactics in both offensive and defensive operations. The French might have succeeded had they coordinated fire and shock in the main assault; and had they made one or more breaches in the Imperialist line, their cavalry might have turned panic into rout.

On the other hand, Colonna’s defence depended on all four arms: his artillery redoubts, his deep line of arquebusiers, his pikemen in close support, and his cavalry guarding the rear.

We learn much from this battle about the Renaissance revolution in war in the early 16th century. •

All images: WIPL, unless otherwise stated.