In the summer of 1996, two students stumbled upon what would become one of the most controversial remains in North America—a skeleton called Kennewick Man. The 8,500-year-old skeleton has been the focus of a fierce debate between Native Americans and scientists. Tribes living in the region where Kennewick Man was found wanted to rebury the skeleton because they claimed he was their ancestor, but scientists later challenged Kennewick Man's Native American ancestry and won their legal case to study the skeleton. The research the ruling was based on concluded that Kennewick Man most closely resembles Japanese Ainu and Polynesian populations. However, a new study, published in Nature, suggests that the scientists were wrong. DNA analysis reveals that Kennewick's genetic makeup leads “unerringly” to Native Americans.

There is a painful history of Native American remains being taken, with little regard to their beliefs and customs, and sent to labs to be studied. As Douglas Preston, from Smithsonian Magazine, explained earlier last year: “The early history of museum collecting of Native American remains is replete with horror stories. In the 19th century, anthropologists and collectors looted fresh Native American graves and burial platforms, dug up corpses and even decapitated dead Indians lying on the field of battle.”

This prompted the 1990 Native American Graves Protection and Repatriation Act (NAGPRA), which gave Native Americans the right to take possession of ancestral human remains and give them the respectful burial they believe is due. Under NAGPRA, a coalition of Columbia River Basin Indian tribes claimed right to Kennewick Man.

Researchers who challenged this claim underwent a long legal battle, which reportedly involved 93 government attorneys. In 2002, the court ruled that the remains were not related to any living tribe and thus NAGPRA didn’t apply. One of the researchers at the heart of this case, Douglas Owsley from the Smithsonian Institution, told Smithsonian Magazine: “I just felt this was one of those extremely rare and important discoveries that come once in a lifetime. If we lost it”—he paused. “Unthinkable.”

Shortly after the court case, a team of scientists began to examine Kennewick Man. The study, which was eventually published in 2014, used isotopic, anatomical and morphometric analysis to determine Kennewick Man’s origin and concluded that the skeleton was distinct from modern Native Americans. The new study, led by Professor Eske Willerslev from the University of Copenhagen, compared the genome sequence of Kennewick Man to the genomes of contemporary human populations and found that today’s Native Americans are his closest living relatives.

“Our study further shows that members of the Confederated Tribes of the Colville Reservation that belongs to the Claimant Plateau tribes of the Pacific Northwest, who originally claimed him as their ancestor, is one of the groups showing close affinities to Kennewick Man or at least to the population to which he belonged,” Willerslev said in a statement.

While the exterior of the skeleton was well preserved, the DNA sample researchers used was highly degraded and dominated by DNA from soil bacteria and other sources. “With the little material we had available, we applied the newest methods to squeeze every piece of information out of the bone,” said first author Morten Rasmussen.

Researchers had to be careful that the ancient DNA sample was not contaminated from modern DNA. Associate professor Anders Albrechtsen, from the University of Copenhagen, who was involved in the bioinformatics element of the investigation, claims the study was “successful in obtaining human DNA that almost exclusively was of ancient origin.”