King Karl Albert refused to accept the defeat of the previous year against Field Marshal Radetzky and saw the uprising of the Hungarians as a given occasion to continue the war.

A coup in February 1849 against Grand Duke Leopold II of Habsburg in Tuscany gave the necessary reason to continue the Italian War of Independence.

The Piedmontese army wanted under their new chief of staff, the Polish General Wojciech Chrzanowski, to take action directly on Milan and so they could get the population of this city to revolt like last year.

Field Marshal Radetzky decided on March 21 to concentrate his forces at Mortara and then turn against either Vercelli or Novara; here or there he wanted to meet the main army of the Piedmontese.

Meanwhile, the II Corps of the Austrians under General d'Aspre and the division of Archduke Albrecht von Österreich-Teschenwhich started the attack at 5:00 p.m. Mortara was quickly stormed and the Piedmontese were forced to retreat at all points.

The poorly trained Sardinian troops fled back to Mortara, pursued by the Austrians, of whom three battalions occupied the entrance to Garlasco.

Despite the victory of Mortara, Field Marshal Radetzky still couldn't take advantage of the resulting favorable situation, since he chose to attack the city of Vercelli, which he regarded as the "main camp" of the Piedmontese army.