Screenwriter Jorge Semprún's life and work as a member of the central committee of the Spanish Communist party from 1954 to 1965 are the basis of the character Diego Mora played by Yves Montand actions and thoughts in 'La Guerre est finie'.
The Spanish-born protagonist of this film, played by Yves Montand, goes by many names. The passport he carries at the beginning of the narrative bears a French name, René Sallanches, but this actually belongs to a Frenchman who, out of political sympathy, had allowed the hero to borrow his passport and (temporarily) substitute his own photo for Sallanches'. To Sallanches' daughter Nadine (played by Geneviève Bujold), the hero identifies himself as "Domingo" (the Spanish word for "Sunday") and she thereafter playfully nicknames him "Dimanche" (French for "Sunday"). To his revolutionary friends and acquaintances, he is known as "Carlos," but this is clearly a code name to protect his identity in case any of his comrades are captured and tortured. To his mistress Marianne (played by Ingrid Thulin) - the person to whom he is closest - he is known as Diego, yet she, when they are alone together, recalls that she had previously known him by several other names: Francisco, Rafael... and Carlos. So although the character is identified in the cast list (and presumably in the script also) as "Diego Mora," the audience has no way of knowing, even at the end of the movie, whether that is his actual name.
The plot of this movie, which is set in the mid-1960s, deals with an organization of Leftist revolutionaries, to which the hero belongs, who are struggling to overthrow Spain's Fascist dictatorship, led by Generalissimo Francisco Franco, who had already ruled Spain for nearly three decades. Some years prior to his death in November 1975, Franco sought to reestablish the monarchy, which had been overthrown in the early 1930s, by appointing Juan Carlos of the House of Bourbon as his designated successor; later that same month, Juan Carlos became king. Most observers expected King Juan Carlos to carry on Franco's dictatorship - Franco himself no doubt had assumed this. But the monarch shocked nearly everyone by quickly transitioning the country to a pluralistic democracy with a Constitution, ending the dictatorship. So Franco himself inadvertently accomplished what the real-life Left revolutionaries, working tirelessly for years, had failed to do: he ended Spanish Fascism.