The journey of dentalium: Tracing ancient trade routes along the Upper Missouri

The Mandan, Hidatsa and Arikara nations centered across three regions along the Missouri River, forming the most crucial trade complex in what is now considered the Midwest. The Arikara established themselves at the Grand River complex, the Mandan situated themselves around the Heart River and the Hidatsa formed a hub along the Knife River.

Along this trade network, dentalium shells, prized for embellishment and adornment, found their way into the lives of women from Native nations, including in the present-day Midwest.

The Mandan’s commercial empire

The Mandan formed a trade hub at the confluence of the Missouri and Heart rivers, establishing a string of large villages along the Missouri with as many as 15,000 by 1450. The bustling hub became known as the “Marketplace of the Central Plains,” and the Mandan created what was to be the forerunner of the trading posts that came later to the area, exchanging their abundant harvests of corn and other agricultural products.

Michael Barthelemy, director of Native American Studies at Nueta Hidatsa Sahnish College, says the three tribes were at the epicenter of trade in the Upper Missouri. He has been studying the history of the U.S. West with a focus on the Mandan, Hidatsa and Arikara. The tribes had intricate linkages between one another, he said, which can be seen in the movement of traded goods.

“We have copper coming in from the Ohio River Valley, pipestone coming in from Minnesota, dentalium, of course, coming from the Northwest to where we’re situated along the Missouri River,” said Barthelemy. “We also have abalone shells coming in from California. And so you have this really extensive trade network.”

Following the Shell Trade

Paul Picha, the former chief archaeologist in the Archaeology and Historic Preservation Division at the State Historical Society of North Dakota, conducted research at the Knife River Indian Villages, a former Mandan and Hidatsa trading hub. Dentalium was traded at least as early as 1400, according to Picha. “Those Northwest Coast groups would gather those shells probably by the thousands or tens of thousands,” Picha said.

By 1800, there was a fair amount of dentalium on the Great Plains. “We do know those trade route systems of Pacific Ocean shells, like dentalium, abalone and mother-of-pearl, made their way through North Dakota throughout the 19th century,” Picha said.

Indigenous groups from the Pacific Northwest, primarily around the Vancouver Island region, would harvest dentalium.

“Tribes on the Northwest coast would gather it, clean it and prepare it, then come eastwards with it,” said Dakota Wind Goodhouse, a Native American Studies and U.S. History instructor at United Tribes Technical College. “Some tribes like the Clatsop would ascend the Columbia River and they would reach a secondary trade area, like an intertribal rendezvous point.”

Travelers might trade off dentalium to the Nimíipuu, or the Nez Perce, who would ascend the Snake River. From there, the Nez Perce would come to the Great Plains. “I don’t know if they came every year, but they came with some regularity that they’re familiar with our landscape,” Goodhouse said.

Another passage dentalium would have taken is through Yellowstone Country. Goodhouse said the likeliest trade route before going down the Missouri River would have been through the Yellowstone River, which is also known as the Elk River to the Lakota, Crow, Blackfeet, Mandan, Hidatsa and Arikara. Other tribal intermediaries, such as the Crow, Lakota, Blackfeet, Cheyenne, Assiniboine, Ojibwe and Cree traded the shell across regional centers.

When Women Controlled the Trade

The exchange of dentalium contributed to economic success in trading villages. Now preserved as the Knife River Indian Villages National Historic Site, located near Stanton, North Dakota, the village sites here were most prosperous in the 1700s, before the end of the Plains Era.

The trading hub ran under a village economy, characterized by an agricultural-based society. The Mandan and Hidatsa grew their food in the rich floodplain, which made agriculture the center of their economy. Women raised corn, beans, squash and sunflowers, while men hunted bison, deer and small game for meat, hides, bones and sinew. Natives residing there lived in earth lodge villages along the Knife River. Pre-colonization, women played a significant role in the economic side of society.

For the Mandan and Hidatsa people, “women are the ones who own the property and are dictating a lot of these trades from behind the scenes,” Barthelemy said. “Men are the ones that are engaged in this trade in a one-on-one manner. You have this acquisition of foreign trade goods brought within the household.”

With more European fur traders appearing in areas such as the Knife River Indian Villages after 1750, the people residing in those villages began to diversify in culture. Hidatsa and Mandan were the most common languages, but there were also Lakota, English, French and German speakers. But long before those other cultures arrived, the Mandan, Hidatsa and Arikara people had established these thriving trading centers.

The Network Unravels

The smallpox epidemics of 1781 and 1837 brought all of that to a halt, wiping out around 90% of the Mandan people and 60% of the Hidatsa and leading to a collapse of the region’s trading centers. Consequently, “1781 leads to the abandonment of the Heart River complex by the Mandan, moving north in close proximity to the Hidatsa,” said Barthelemy. “It’s also this abandoning of an earlier Arikara complex, moving in and solidifying around the Grand River region.

“We have to keep in mind these are just but two of the epidemics that are moving like shockwaves across these trade networks. And with the loss of population comes a weakening of the dominance within the interior region.”

Compounding the situation was the Arikara War of 1823, a conflict fought between the U.S. and the Arikara after an attack on fur traders from the Rocky Mountain Fur Company. The combination of disease, war, and, later, assimilation would impact and eventually put an end to the trade routes.

Trade still continued in villages like Knife River until Native peoples were forced into reservations in the 19th century. Nonetheless, dentalium has remained a part of American Indian culture, but an entirely new trade route has emerged. Shells are no longer mass-harvested from the Pacific Northwest, but this time, they arrive in artists’ hands from the Arabian Sea.

More Than Money

Despite changing supply chains and rising costs, dentalium continues to hold deep cultural significance, serving as a symbol of resilience and a connection to Indigenous heritage. Interestingly, many of the ancient trade routes that carried these shells across the continent align with modern transportation corridors, a testament to the enduring importance of these pathways in facilitating human connection and exchange.

Nowadays, dentalium is available for purchase mainly online. Most sellers buy their stock from India and across Southeast Asia rather than locally due to limited availability in the American Northwest. But even as supply chains change and prices rise, people continue to wear dentalium today because of its symbolism, history and cultural pride.

“Dentalium, when you see it among members, [signifies] wealth and prominence,” said Barthelemy. “And it’s not really wealth and prominence in the way that you think about it in the Western society — it’s more so they’re showcasing their affiliation with the community.”

The journey of dentalium shells across the continent illuminates a sophisticated network of Indigenous trade that predated European arrival. “Oftentimes people become a little confused in the idea that, oh, Europeans created this trade network, but, no, they’ve just interjected themselves in this existing network among tribes,” said Barthelemy.

This understanding reshapes the predominant view of early North American commerce, revealing Indigenous peoples not just as participants in trade but as its architects. Today, each dentalium shell serves as a reminder of these ancient pathways and the complex societies that created them.