The letters were found amongst a collection of documents by Italian poet Gianni Diecidue when they were donated the state by his heirs, Corriere del Mezzogiorno reported.

Writing to Sicilian Friar Giovanni Pantaleo in the 1860s and 1870, Garibaldi calls on the priest to support the unification of Italy and be wary of the Vatican’s influence.

In 1860 Garibaldi’s army marched on Sicily and then Naples, overthrowing the monarchy and founding the Italian nation the following year.

While the military hero is well-known for his anti-clerical view, Lucy Riall, a history professor at the European University Institute in Florence, told The Local that the significance of the letters lie in who they were written to.

“[Pantaleo] was a radical nationalist priest. He joined Garibaldi and preached to the people of Sicily that they must join the revolution against the old regime and the power of the church.

“The letters might enable us to know more about this radical character who has largely been forgotten,” added Riall, who wrote Garibaldi: Invention of a Hero.

Although famed for his acts 150 years ago, Riall said Garibaldi’s political style lives on in Rome.

“He’s in many ways an early protagonist of the popular leader who uses the media to get his message out there and be someone who was easily recognized,” she said, particularly as illustrated magazines and affordable novels began to emerge in the 19th century.

“But whereas popular leaders are now more right-wing, he was a democratic leader. In Sicily in 1860 he enjoyed almost total power but gave it all away to retire to his farm."

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