The United States and Russia haven't been cooperating much in these days of heightened tensions, but the U.S. Embassy in Moscow this week returned 28 valuable historical documents to Russia.

They were stolen from Russian collections and archives during the turbulent 1990s, in the wake of the Soviet collapse. The documents were believed to be stolen by Russian insiders and then made their way to U.S. dealers and auction houses.

U.S. and Russian officials met at the American ambassador's residence to exchange friendly words and speeches of thanks.

The reason for the ceremony was on display in an adjoining room — a whole table covered with the stolen goods.

They included historical documents and drawings — some of them signed by Russia's most powerful rulers, says Jason Cassidy, a deputy attaché at the embassy from the U.S. Department of Homeland Security.

"Members of the imperial family, the Romanovs, Alexander the First, Alexander the Second, Peter the Great, Josef Stalin, who signs his documents in red crayon, by the way," he says.

U.S. Agents Tracked Them Down

Cassidy's department has been working with Russia for the past dozen years or so to recover stolen Russian documents that had come up for sale in the United States.

He says some of his agents have gotten really good at it.

"One of those astute investigators noticed at a local gallery in the U.S. that there was an alleged degree signed by Peter the Great, and just based on experience knew that, 'You know what, there's probably no way that that got out of Russia legally,'" he says.

"So we reached out to the Ministry of Culture," he adds. "Of course, the Ministry of Culture said, 'Nah, nah, everything's good. I think we have it, but you know what, we'll do an audit of the gallery just to double check.' We got a call back maybe a week or two later. 'Oh my God, you'll never believe it. It was stolen and replaced with a replica. We don't even know how long it's been gone.'"

At the ceremony, some of Russia's top document specialists arrived to take charge of the valuables.

Tatiana Goryacheva, the head of the Russian Archives of Literature and Art, said she hoped the publicity surrounding the event would encourage respectable collectors to return any documents they think might be stolen.

The event drew a lot of Russian media, and U.S. Ambassador John Tefft says it's refreshing to have coverage of cooperation between the two countries.

"It shows America cares about Russian history, Russian culture, and we're also a nation of laws," the ambassador says. "And when the bad guys stole these things from the Russian archives, we caught them, and we're bringing it back. That sends a good message."

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