The film is directed and co-written by Giuliano Montaldo, and stars Gian Maria Volonté and Riccardo Cucciolla in the title roles.

At the 1971 Cannes Film Festival, Montaldo was nominated for the Palme d'Or and Riccardo Cucciolla won the Best Actor Award.

The film is based on a stage play of the same name, written by Mino Roli and Luciano Vincenzoni, which was first performed in Rome in 1960, and was a moderate critical and commercial success.

Gian Maria Volonté and Riccardo Cucciolla had both starred in the original play, albeit in different roles (the former as Sacco and the latter as Celestino Madeiros).

After obtaining the rights, Arrigo Colombo and Giorgio Papi wanted Yves Montand and Lino Ventura to play the lead roles.

The film's soundtrack was composed and conducted by Ennio Morricone, with song lyrics by the American folk singer Joan Baez.

For the lyrics of "The Ballad of Sacco and Vanzetti Part 1," Baez made use of Emma Lazarus' 1883 sonnet The New Colossus, the lines of which appear inscribed on a bronze plaque in the pedestal of the Statue of Liberty.

[6]"Here's to You" plays in the 1978 film Germany in Autumn, accompanying footage of the funeral for Red Army Faction members Andreas Baader, Gudrun Ensslin, and Jan-Carl Raspe, who had committed suicide.

Ebert wrote, [Montaldo] has already made us aware of the crowds surging outside the courthouse, and in the [contemporary newsreel sequences on the] streets of world capitals.

They are blandly evil, cutout figures, as are all of the intimidated witnesses, bigoted observers and political opportunists who swarm across the film.Canby also decried the film's soundtrack, which he described as "absolutely dreadful," with Baez's voice "used to certify the movie's noble intentions, but through the cheapest of means.

"[11] The film, according to the testimony of its director, significantly contributed to the historical and moral rehabilitation of the two in the United States of America: when in a public ceremony held on 23 August 1977, the 50th anniversary of their execution, the governor of Massachusetts Michael Dukakis officially recognized the judicial error and the malice of the magistrates, the director Giuliano Montaldo was "invited to rehabilitation for having contributed to it.