Carlo Alberto Rosselli was an Italian political leader, journalist, historian, philosopher and anti-fascist activist, first in Italy and then abroad. He developed a theory of reformist, non-Marxist socialism inspired by the British Labour movement that he described as "liberal socialism". Rosselli founded the anti-fascist militant movement Giustizia e Libertà. Rosselli personally took part in combat in the Spanish Civil War, where he served on the Republican side.

Gaetano Salvemini was an Italian socialist and anti-fascist politician, historian, and writer. Born in a family of modest means, he became an acclaimed historian both in Italy and abroad, particularly in the United States, after he was forced into exile by Benito Mussolini's Italian fascist regime.