How Inca Decimal Administration Worked

Understanding Inca decimal administration has been elusive because Spanish administrators recorded only partial descriptions of Inca practice and failed to grasp the logic and principles which guided it. Decimal administration can be reconstructed in broad outline from two native accounting records, pre- served on knotted devices known as quipos. Once an overview of the system is gained, the logic and principles which informed Inca practice become perceptible. This in turn enables an assessment of the impact of Inca authority on the politi- cal organization of the Andean area. The Incas did not simply reorient existing political organization to meet their own ends, but reorganized it to be the struc- tural equivalent of local authority elsewhere and, in the process, authored a new territorial configuration in the Andes. The Incas conquered and held a large territory during the century before the Spanish arrival in the Andes. That they organized the diverse An- dean population into decimal units for administrative purposes was not doubted by sixteenth-century Spanish writers, all of whom were aware of the magnitude of the task of running an empire in the Andes. Yet these writers, our nearest witnesses to Inca administration, say almost nothing about the operation of decimal administration. Four centuries later, and more than a century after the beginnings of ethnohistorical inquiry, we still have no workable idea about how the Incas organized their empire