Scientists have long suspected that the ancient indigenous groups of Alaska traded with peoples of Eurasia, highlighted by oral histories and Asian-influenced design. But researchers lacked solid evidence, until now.

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A study, published in the Journal of Archaeological Science, documents the discovery of a metal bead and a belt buckle that date from between 1100 to 1300—a period of time when the Thule people, ancestors of the modern Inuit, inhabited the region.

This discovery shows that indigenous people in North America were likely interacting with the "Old World" from both sides of the continent, lead author of the study, H. Kory Cooper tells Smithsonian.com. On the east coast they traded with the Norse, while on the west coast they traded across the Bering Strait, he explains.

Archaeologists John Hoffecker and Owen Mason of the Institute of Arctic and Alpine Research at the University of Colorado, Boulder, found the objects while excavating six Thule houses on Cape Espenberg, a remote outpost on the Seward Peninsula jutting into the Bering Strait.

Among the thousands of artifacts collected from the Thule dwellings were six metal objects including two bone fishing lures with metal eyes, a copper needle and a sheet copper fragment. But what intrigued researchers were two objects made of leaded bronze: a cylindrical bead that may have been used as part of a whistle or noisemaker and a buckle connected to a scrap of leather.

The pair took the artifacts to Cooper, who is an expert in Arctic and Subarctic metallurgy at Purdue University. He found that the bronze objects are an alloy of copper, tin and lead. The buckle, which is similar to those used in China as far back as 400 B.C., also appears to have been made using a mold.

While the Thule people did occasionally work with native copper and some iron, they did not use alloys or molds. So the presence of these seemingly ordinary objects suggests that they must have come from outside the region and suggest that Alaskan trade with Asia could have begun as early as the 1100s.

Of particular importance was the tiny scrap of leather attached to the buckle, says Cooper. Without it, the team would not have been able to get dates for the artifacts.

And the bronze is not the only item linking the site to Asia. The researchers additionally found obsidian objects at the site that are traceable to the Anadyr River valley in Russia, which drains into the Bering Sea, reports Owen Jarus at Live Science.

Though European and American merchantmen did not reach the Bearing Strait until the 18th and early 19th centuries, researchers have long suspected that the Thule people traded with civilizations in China, Korea and Russia.

Jarus says plate armor made of whale bone and iron discovered by Smithsonian anthropologist Henry Collins on St. Lawrence Island in the 1930s suggests locals may have been influenced by east Asian designs. An ancient Chinese journal also talks about acquiring walrus and narwhal ivory from peoples north east of that region.

This new evidence strengthens these claims and demonstrates the possible early routes of trade with the New World, says Cooper.

Though this has been a long-held belief among archaeologists, the remoteness of the dig sites in Alaska and the brief excavation season left researchers with little material proof.

Even so, with the mounting evidence from other finds, Cooper remained confident that eventually something would surface. “In my mind it was just a matter of time before we found something like this.”