The world has been introduced to the true face of Julius Caesar with the discovery in a river in southern France of a bust that was sculpted in the lifetime of the Roman leader.

The marble sculpture, found in the bed of the Rhône in the town of Arles, has been authenticated as a realistic likeness of Caesar, wrinkled and balding in his fifties and probably modelled from life.

“It is the only known bust of the living Caesar, except for the Mask of Turin, which was made just before or after his death, said Luc Long, the Ministry of Culture archaeologist who found it along with other treasures last autumn. “Even in Rome, no one has found a portrait of the living Caesar,” he added.

The bust, which has a broken nose, dates from between 49 and 46BC, the period when Caesar founded the Roman colony of Arles, to thank the town for helping him to conquer the nearby port of Marseille. Caesar used Arles as a base for his campaign against Pompey, his rival.

Mr Long speculated that the bust may have been thrown into the river just after Caesar was assassinated by Brutus and fellow conspirators in 44BC “because it wouldn’t have been a good idea to show you were his supporter”. Experts agreed that the life-sized head matched the known official portrait of Caesar, which featured on coins struck in his lifetime.

“These really are his features. I recognised them immediately,” said Mr Long. “It is a new image, with the realism of the period, before the conventional representations of a divine Caesar. He has a long neck, wrinkles showing his age, the prominent Adam’s apple, the high and wide forehead and marked baldness.” Michel L’Hour, director of the underwater architecture institute at Marseilles, to which Mr Long belongs, said that the bust became apparent after a movement in the silt bed of the Rhône.

“It is very well preserved, as items found under water often are. It is very realistic. Not at all prettified. Caesar’s features are hard and ageing. That makes it remarkable. It is much more human than the stereotypical statues which show him with laurel crowns. It is the oldest bust of Caesar and it was doubtless sculpted to honour him as the patron of the town of Arles.” Christine Albanel, the Culture Minister, congratulated the archaeologists on finding a unique object that enriched the world’s heritage.

Ms Albanel called the Caesar bust unique and “an outstanding discovery in a class of its own”. Her ministry called it “the oldest representation yet known of Caesar”. The other items found by the underwater team were a marble statue nearly six feet tall of the god Neptune dating from the beginning of the third century AD, and smaller bronzes, one of a Greek satyr with its hands tied behind its back.

Mr L’Hour said that it was common for residents of ancient towns to throw unwanted goods into the river.

“The Caesar bust may have been on display in a public institution or in a patrician villa. One can imagine that with the assassination of Caesar, they tried to get rid of it quickly by throwing it into the river because he had become an embarrassing person to venerate. We do not have much knowledge of Caesar’s time in Arles,” he told The Times.

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