Mussolini's secret mistress and their love child come to life in a film by Italian director Marco Bellocchio showing in competition at the Cannes film festival, AFP reported.
"Vincere" recounts the ends to which the dictator went to hide the mother and child who potentially could have put a brake on his rise to power in pre-war Italy.
"The Mussolini I talk about is not the affectionate pater familias sometimes shown on television whose only mistake was to ally himself with Hitler," Bellocchio told the leading Italian daily Corriere della Sera.
Two works inspired the film, "Mussolini's Wife" by Marco Zeni and "The Secret Son of Il Duce" by Alfredo Pieroni.
"He's a violent, calculating, merciless man, even towards the woman he loved and his own son," said Bellocchio, 69.
In 1914, Mussolini, then aged 31, belonged to the Socialist Party, directed the daily newspaper Avanti! and had lived for two years in northern Milan with Rachele Guidi, who would later become his wife.
But he chalked up numerous affairs, including with Ida Irene Dasler, a strong-willed woman three years his senior who ran a beauty salon.
Ida staunchly supported him when he was expelled by the Socialist Party for backing Italy's entry into World War I.
She even sold her salon to help him found his own newspaper, Il Popolo d'Italia (The People of Italy).
Some journalists and historians say the couple married in 1914, but this is disputed.
Ida was seven months pregnant when Mussolini left for the front in August 1915. She gave birth to their son Benito Albino on November 11.
She informed Mussolini of the news in a letter, but received no reply.
Instead, she heard he was hospitalised with jaundice and went to his side with the babe in arms.
The day before, Mussolini had married another lover, Rachele, at the hospital.
Nevertheless he promised Dasler that he would recognise their child, and he followed through a few months later before returning to the front.
He also sent a monthly allowance for the boy.
But Mussolini soon turned his back on his former mistress, ignoring her letters and putting her under police surveillance.
The young mother doggedly continued to write to him and complained of her situation to the authorities.
Once Mussolini rose to the height of power in November 1922, he ordered even closer surveillance of Dasler lest she make more waves.
In 1926, when Il Duce had become undisputed dictator, muzzling the press and the opposition, Dasler was arrested and thrown into a mental hospital. The boy was forcibly taken from her and put in the care of a tutor.
Dasler, after being moved to two more institutions and never allowed visits or correspondence, finally died aged 57 in 1937.
The boy, who was 11 when his mother was first sent to an institution, studied at boarding school until he was 18 when he entered the marines.
Although Mussolini had no contact with him, he had a close eye kept on the boy.
The fact that the young Benito kept in touch with his mother's family troubled the authorities, who sent him without warning to Asia in 1934.
The next year when Benito returned to Italy he was hospitalised, and like his mother transferred to a psychiatric facility in 1936, where he died six years later, aged only 26.
He and his mother were both buried in unmarked graves.