When Colorado State University doctoral student Robert Madden left his career as a trial lawyer, he saw an opportunity ahead of him: to master his “original love” and undergraduate study of archaeology.

Madden’s recent study, published in “American Antiquity,” displays his efforts to contribute to the field of archaeology by suggesting Native American dice, games of chance and gambling, have existed since the end of the Ice Age, 12,000 years ago. The findings predate the earliest Old World dice by 6,000 years. Madden described what drew him to these artifacts. 

“(I thought), ‘Wow, this is really interesting that they have their own Indigenous games of chance,’ which really implies a basic understanding of randomness and some of the things that are really important to our modern society,” Madden said. “I thought, ‘(I’ve) got to find a way to solve this riddle of how do we track this back to its origins? How do we see how old this really is?’”

The dice don’t reflect modern images; instead, they’re two-sided and made of wood and bone. Derived from Stewart Culin’s 1907 compendium, “Games of North American Indians,” Madden used these characteristics, alongside different shapes, sizes and marks that distinguished each side, to create an objective test used to identify the dice.

Ultimately, Madden spent three years digging through site reports, online databases, library stacks and in-person collections at The Smithsonian Institution, the University of Wyoming Archaeological Repository and the Denver Museum of Nature and Science. All in all, he identified over 600 dice from 57 archaeological sites, including items that may have been classified as gaming pieces or previously miscategorized.

Contributions from Madden’s study include his methodology, said Michael Pante, chair of CSU’s department of anthropology and geography. The department’s research expenditures, which ranked top five within its field during 2025 in the United States, are essential for getting students involved in high-profile research like Madden’s dice study, Pante said.

The study took place within the department’s Center for Mountain and Plains Archaeology, which is directed by Professor of anthropology Jason LaBelle.

Concentrated in the western parts of the country that straddle the Rocky Mountains, the dice span in age, creating a continuous timeline that can be followed step by step. Madden said the earliest dice appear in the late Pleistocene Folsom deposits in Wyoming, Colorado and New Mexico. To this day, Indigenous people still make and play with these dice.

The study’s dice predates counterparts, suggesting Native American societies took some of the earliest steps in engaging with concepts such as probability and randomness; however, its results also provide deeper implications about Native American societies. For one, the dice played a social role, connecting different ethnic and language groups, which is significant because they were used by mobile hunter-gatherers.

“The dice became a way for people that don’t know each other well, that don’t have these preexisting relationships to come together to exchange, to meet, to talk,” Madden said. “It’s because there’s this shared understanding of the game. We both understand the game. We both understand that it’s fair. We both understand that we can come together in a way that doesn’t require a relationship, and it allows us to exchange things in a very efficient way.”

The dice are examples of harnessing randomness to bring people together.

“(The dice are) super adaptive; it had to be.” Madden said. “Why else would it last for 12,000 years? Things don’t last that long in societies if they don’t perform a really important function.”

Robert Weiner, a postdoctoral fellow and lecturer at Dartmouth College who primarily studies societies in the Chaco Canyon, home to ancestors of Pueblo and Navajo peoples, described Madden’s study as innovative.

“He’s thinking about big questions, and he’s bringing intellectual contributions of Native societies that have for so long been marginalized and sort of framed in ways that are really dehumanizing,” Weiner said. “His project is really showing these amazing contributions (Native societies) made, not just within North America but really the history of humanity. It’s only been in the recent years that Native history is getting the coverage it deserves along with other sort of more famous societies in the ancient world.”

Weiner has also studied gambling in the Chaco region, which ties into Madden’s study.

“In the current West, we often think of gambling as just a recreational leisure activity, … but it really has all these economic, religious and social dimensions traditionally in Native societies,” Weiner said. “So for him to demonstrate not only a geographic spread, but how deep that goes in time is a wonderful contribution to the archaeology of North America and also the world.”

Despite being a side project during his Ph.D. journey, Madden’s dice study has garnered attention, spanning coverage from outlets such as NBC and CNN, which he said has been a crazy experience.

“That’s what’s kind of one of the things gratifying about this paper — to feel like maybe I’ve made some contribution to North American archaeology,” Madden said. 

Reach Chloe Rios at science@collegian.com or on social media @RMCollegian.