Research on the chronology of the Inca Empire

As part of the Capacocha project, advanced research is being conducted on the chronology of the development of the Inca Empire (Tawantinsuyu), with an emphasis on the period of its greatest expansion—from the late 14th century until the arrival of the Spaniards in 1532. The goal of the project is to precisely determine the dates of key historical events through the use of radiocarbon and dendrochronological methods.

Although the Inca era is not distant in time, there is a lack of consistent written sources created by the Incas themselves. The information mainly comes from accounts of Spanish chroniclers, which—as recent studies show—are often inaccurate. In particular, the dates concerning the expansion of the Inca Empire require verification. Data from research in the Machu Picchu region suggest that the expansion began much earlier than earlier estimates based on chronicles indicated.

The project focuses on the analysis of wooden artifacts and organic remains originating from archaeological contexts in the Arequipa region of Peru and northern Argentina.

The use of wiggle-matching and Bayesian modeling methods allows for obtaining more precise radiocarbon dates—with accuracy greater than traditional methods, which typically have an error margin of about ±15 years. Special attention is given to creating so-called “floating chronologies,” which can serve as a foundation for building a more accurate timeline of events from the pre-Hispanic period. „pływających chronologii” (floating chronologies), które mogą stać się podstawą do budowania dokładniejszej osi czasu wydarzeń z okresu przedhiszpańskiego.

Thanks to dendrochronological analyses and dating of plant remains (e.g., grasses or food residues), it is possible to gain a better understanding of the social and political changes associated with the capacocha ritual. The project also takes into account historical accounts concerning the reigns of rulers such as Pachacuti Inca Yupanqui, Topa Inca, and Huayna Capac, comparing them with new empirical data.

The research conducted within the Capacocha project has the potential to significantly contribute to the reconstruction of the history of one of the most important pre-Columbian empires, combining methods of the natural sciences with the interpretation of historical and archaeological sources.

The chronology project is led by Dr. Dominika Sieczkowska-Jacyna and funded by the National Science Centre, Poland, under the Sonatina 8 competition (2024/52/C/ST10/00061).

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