With this family background, it is scarcely surprising that Leonida turned to left-wing politics as a student at the University of Bologna, where he earned his law degree at the age of 20.

He promptly went on to found the Italian Reformist Socialist Party (PSRI), with Ivanoe Bonomi (a future prime minister of Italy) and Angiolo Cabrini [it].

[1] Bissolati strongly advocated Italy's entry into World War I on the side of the Triple Entente, while his former socialist friends favoured neutrality.

Attacked from all sides, he resigned from the government and withdrew from politics in December 1918, although subsequently he met with Wilson and urged that Italy not be given Fiume or the Dalmatian Coast.

[1] On 18 December 1974, the Leonida Bissolati Lodge, a Masonic centre affiliated with the Grand Orient of Italy and named in his honour, was founded in Cremona.