After the battle of Montebello of 20 May 1859, the Franco-Piedmontese army moved towards Novara, aiming to reach Milan, the capital of Lombardy-Venetia, the Austrian province in northern Italy. Part of the Piedmontese forces advanced to Robbio to cover the right flank of the allied army.
On 30 May the Piedmontese crossed the Sesia river and, after a hard fight, managed to take control of Palestro, Vinzaglio, and Confienza. The following day, in order to test the enemy's strength, Austrian field-marshal Friedrich Zobel ordered two of his infantry divisions to attack Palestro. The 4th Piedmontese Division under general Enrico Cialdini took position between Palestro and the road to Robbio, with the 10th Infantry Regiment on his left, the 9th Regiment defending Cascina San Pietro, and the 3rd Zouaves Regiment on his right flank, on an island in the river known as Sesietta. The King of Sardinia-Piedmont, Victor Emmanuel II, was in Palestro and followed the early course of the battle from the town's bell tower.
The Austrian attacked first the Piedmontese line at Palestro, but were pushed back to Robbio. The Piedmontese at Cascina San Pietro were also under heavy attack from Austrian troops from Rosasco. The situation was solved by the rushed attack of the 3rd Zouaves Regiment under Colonel Chabron, who attacked the left flank of the Austrian contingents. The Zouaves were able to reach the enemy's artillery, defended by the 7th Tirolese Hunters Regiment. Then they launched a bayonet attack against the four infantry battalions of the 12th Regiment "Archduke William". The positions conquered by the French units were immediately reinforced by Italian troops, led personally by Victor Emmanuel, which arrived in time to repel an Austrian counterattack.
After the Franco-Piedmontese troops had strengthened their bridgehead over the Sesia river, Zobel, despite its numerical superiority, retired towards Robbio. His decision was motivated by the fear that French units under general Canrobert, which had just reached the left bank of the Sesia, could cut in two his corps.