The "Llullaillaco Maiden" — a teenage girl whose mummified body was found atop a frigid volcano in Argentina — was sacrificed centuries ago by the Inca. Now, a new analysis of plant remains in her burial is helping archaeologists pinpoint the historical events that led to her death over half a millennium ago.

In 1999, archaeologists discovered the remains of three mummified Inca children — one teenage girl, and a boy and girl each around 7 years old — just below the summit of the Llullaillaco volcano in Argentina near its border with Chile. Analysis of the mummies over the past two decades has shown that the children were fattened up with gourmet food and plied with alcohol and coca (a plant from which cocaine is derived) before they were led to a subterranean shrine on the freezing, windy summit and left for dead.

Even though these mummies, dubbed the "Children of Llullaillaco," are incredibly well preserved, the exact date they were sacrificed has remained unclear. A radiocarbon analysis conducted in 2007 on hair samples from the mummies placed their deaths sometime between 1430 and 1520. To narrow down this date and link it to known political and climatic events, an international team of researchers radiocarbon-dated the botanical remains found in the burial. They published their results June 5 in the journal Archaeometry.

The Llullaillaco Maiden, also known as La Doncella, is the name given to the mummy of the teenage girl. Due to the many funeral offerings she had been given, archaeologists think she may have been the main sacrifice and was accompanied in death by the two younger children as attendants. Included in the Llullaillaco Maiden's offerings were corn (Zea mays), cassava (Manihot esculenta) and coca leaves (Erythroxylum coca), whose seeds were carbon-dated to reveal a more precise chronology than the mummies themselves.

The archaeologists found that the botanical remains narrowed down the children's possible date of death to between 1462 and 1507, with the most likely date falling around 1499, during the reign of Huayna Capac, one of the last Inca emperors.

The Inca Empire reached its greatest extent under Huayna Capac, who ruled from 1493 to about 1525, when he died of smallpox introduced by the Spanish. From the empire's capital at Cuzco in southern Peru, the emperor's father, Tupac Inca, had expanded Inca territory south into Chile, while Huayna Capac extended the empire north into present-day Ecuador and Colombia. In 1499, the area around Llullaillaco would have been incorporated into the Inca Empire fairly recently.

"Considering this context, it is plausible that the sacrifice at Llullaillaco may have been enacted as part of such a state-sanctioned campaign [of sacrifices], serving to ritually anchor the Inca presence in the region or to commemorate a significant political event," the researchers wrote in the study. That is, the sacrifice of the three Children of Llullaillaco was likely part of Huayna Capac's effort to maintain cultural cohesion in the vast, diverse Inca Empire.

Colonial-era chronicles do mention that Huayna Capac journeyed to the southern part of his empire, including the northwest region of what is now Argentina, and that he made rich offerings to the gods in the form of child sacrifices, the researchers wrote.

Although it is not possible to definitively link the historical record to the Llullaillaco sacrifice, "placing the event within this historical context not only anchors it to a specific political timeframe but also invites more profound reflection on the potential motives behind such a state-sanctioned event," the researchers wrote.

The Inca practice of child sacrifice in the early 16th century may have reaffirmed imperial authority or sought to maintain cosmic balance during a period of perceived instability just before the arrival of Europeans, according to the researchers.

Similar analyses should be conducted on other child sacrifices, the researchers noted in the study, to learn more about the broader patterns of ritual sacrifice and political power across the Inca Empire.

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