Vatican City - Gauchos, the legendary Argentine cowboys from the vast Pampas of Pope Francis's homeland, are being celebrated in a rare exhibition in no less a place than St. Peter's Square.

Called "Argentina - The Gaucho, Tradition, Art and Faith," it opened on Friday in the Braccio Carlo Magno exhibition space under the square's left colonnade.

But the pope, who is expected to visit it privately, had nothing to do with bringing a taste of his homeland's celebrated cowboy culture to the Vatican.

"It was providence that an Argentine pope was elected in March," said Maria Pimentel, one of the Argentine curators. "It was decided in August, 2012, before Pope Benedict resigned."

"But we are so happy to have an Argentine pope. He knows all about the gauchos," she said at the opening.

The exhibition includes more than 200 paintings, drawings, ponchos, textiles, photographs, musical instruments and artefacts - many more than a hundred years old - recounting the lives and frontier culture of the horsemen and cattle herders.

"Most of these are from private collections and many have never left Argentina before," Pimentel said.

The collection abounds with silver, fittingly so because Argentina derives from "argentum," the Latin word for silver which inspired the European explorers who named it when they heard the area was rich in the precious metal.

One section of the exhibition looks like it descended from equestrian heaven. There are intricately carved silver bridles, silver spurs, silver stirrups, silver bits, silver reins and silver headgear.

There are silver Madonnas and gold chalices, a testimony to the popular religious culture of the area.

One section hosts a collection of "facons," the large, all-purpose silver knives with intricately carved sheaths which the gauchos kept tucked into colorful sashes behind their backs as they rode.

Also displayed are intricate silver and gold "mate," cups with silver straws from which the gauchos would drink a tea made from yerba leaves rich in caffeine and nutrients.

Argentine President Cristina Fernandez gave Pope Francis a silver mate when she met him at the Vatican several days after his election.

Original photographs, many from the late 1800s, document the daily lives of the gauchos - from herding, to playing guitars to passing the long nights, to posing in their Sunday best with silver-laden horses and multi-coloured ponchos.

The exhibition will remain at the Vatican until June 16 and then move to the city of Loreto in Italy's central Marche region, where it will open on July 4 and close on September 1.