new research in ancient history of americaThe leading journal of North American archeology, published by Cambridge University Press for the Society of American Archaeology, presents convincing evidence that the oldest known dice were made and used by Native American hunter-gatherers more than 12,000 years ago. These finds were discovered in the western Great Plains at the end of the last Ice Age, predating the oldest known dice from Bronze Age societies in the Old World by thousands of years.
Colorado State University Ph.D.-led research student Robert J. Madden shows that dice, gambling, and probability games are deeply rooted in Native American culture, dating back at least 12,000 years. The earliest examples are from late Pleistocene Folsom-era sites in Wyoming, Colorado, and New Mexico. These artifacts are more than 6,000 years older than comparable dice found in the Old World.
“Historians have traditionally treated dice and probability as old-world innovations,” Madden says. “The archaeological record shows that ancient Native American groups were intentionally creating objects designed to produce random outcomes and using those results in structured games thousands of years earlier than previously realized.”
The ice age dice looked like this
The oldest specimens identified in the study date back approximately 12,800 to 12,200 years. Unlike modern six-sided dice, these objects were double-sided pieces known as “binary lots.” They are carefully formed from bone into small hand-held shapes, flat or slightly rounded, often oval or rectangular, and designed to be thrown together onto a surface.
Each piece had two distinct sides, characterized by differences in color, texture, or added design, similar to the front and back of a coin. One side served as the “count” side. When thrown, each piece lands showing either side, producing a binary (two-outcome) result. Players cast multiple pieces at once, and the result is determined by the number of pieces that land with the count face up.
“They’re simple, elegant tools,” Madden says. “But they also unmistakably have a purpose. They are not an accidental byproduct of bone processing. They were created to produce random results.”
A new way to identify ancient dice
To move beyond guesswork, this study introduces an attribute-based morphological test, a structured checklist of physical features used to identify dice in archaeological collections. This method is based on a comparative analysis of 293 historical Native American dice sets recorded by ethnologist Stewart Culin in the 1907 American Bureau of Ethnology book Game of the North American Indians.
Using this framework, this study reconsiders artifacts that were previously labeled as potential “game works” or ignored altogether. By applying consistent criteria, Madden was able to determine whether these objects fit the definition of a die.
In many cases, these items have been known for decades but have never been evaluated in broader patterns. With this new approach, this study identified more than 600 diagnostic and probable dice from archaeological sites covering all major periods of North American prehistory, from the late Pleistocene to post-European contact.
“In most cases, these objects had already been excavated and published,” Madden said. “What was missing was not evidence, but a clear, continent-wide standard for recognizing what we were seeing.”
The earliest examples have also been directly examined in museum collections at the Smithsonian Institution, the University of Wyoming Archaeological Archives, and the Denver Museum of Natural Science.
Rethinking the origins of probability
Dice games are thought to be humanity’s earliest structural interactions with randomness, laying the foundations for probability theory, statistics, and scientific reasoning. Until now, scholars believed that these customs originated in complex Old World societies about 5,500 years ago.
New discoveries indicate that its origins were much older and more widespread.
“These findings do not argue that Ice Age hunter-gatherers practiced formal probability theory,” Madden said. “But they intentionally created, observed, and relied on random outcomes in repeatable, rule-based ways that exploited probabilistic regularities such as the law of large numbers. This is important for how we understand the global history of probabilistic thinking.”
long-lasting cultural tradition
This study also highlights how widespread and persistent dice games have been in Native American culture. Evidence of dice has been found at 57 sites in a 12-state area, spanning Paleoindian, Archaic, and late prehistoric periods and reflecting a wide range of cultural traditions and lifestyles.
Madden suggests that this long history points to the important social role of games of chance. “Games of chance and gambling created a neutral, rule-governed space for ancient Native Americans,” he said. “They enabled different groups of people to interact, exchange goods and information, form alliances, and manage uncertainty. In that sense, they functioned as powerful social technologies.”
About research
The article “Pleistocene Probability: Native American Dice, Games of Chance, and the Origins and Antiquity of Gambling” ancient history of americapublished by Cambridge University Press on behalf of the American Archaeological Association.

