Peru tells Yale it wants its Machu Picchu treasures back (after 100 years)

Yale University is embroiled in an escalating dispute with Peru over the return of treasures from the world-famous Incan site of Machu Picchu that are on display as part of the ivy-league university's permanent collection.

Over the years, there have been fitful attempts to find a solution to the contested ownership. It threatens to come to a head later this year, with the departure from office of Alejandro Toledo, Peru's first indigenous President, who has pledged to recover the treasures before he steps down in July.

The dispute recalls other cases where countries are fighting to retrieve artefacts from museums in other countries - most notably Italy's demand that the Getty Museum in Los Angeles and New York's Metropolitan Museum of Art hand back various classical treasures that Rome says is part of Italy's cultural heritage. The items were allegedly looted from sites in Italy and exported illegally.

The provenance of the Machu Picchu material, which arrived completely openly in the US more than 90 years ago, is far more complicated in legal terms. It is also entangled with issues of Peruvian national identity.

Machu Picchu, the fabled "Lost City of the Incas" built at almost 8,000 feet in the Andes, was rediscovered in 1911 by Hiram Bingham, a colourful figure who was variously explorer, aviator, Yale historian, Governor of Connecticut and later a US Senator.

In a series of expeditions between 1912 and 1915, he sent crates of archaeological finds from the site - including bones, pottery, tools and some silver items - back to Yale, with the permission of the government of the day. The key question is whether the material was made over in perpetuity or merely loaned.

The Peruvian government insists on the latter, and is threatening to sue - a process that could find its way from the US courts to some form of international tribunal. "We are convinced we have sufficient proof to win in court," Peru's Foreign Minister, Oscar Maurtua, said last November.

Yale predictably disagrees, saying it has fully complied with agreements signed by Bingham in 1912 and 1916. It has offered to return part of the material, and help with the maintenance in a Peruvian museum. But a compromise looks likely at present.

"This is our patrimony, this is everything to us," David Ugarte of Peru's National Culture Institute told USA Today last month. "Bingham said he was going to study those pieces and give them back. It was clear to all they were going to be returned."

Further complicating matters is an argument over precisely how many items are at issue. Peru claims that the university has 5,000 pieces.

But Yale says the number is "approximately 250 pieces of exhibitable quality" according to a letter sent by Yale to the Peruvian authorities in December. It claimed that Yale had sent back many items as long ago as 1922, and has full title to the rest.