Explosive Expansion, Sociotechnical Diversity, and Fragile Sovereignty in the Domain of the Inka

Societies of the late prehispanic Andes—the Inkas principal among them—have long figured as “exceptions to the rule” in social evolutionary schemata, in large measure because they seemingly lacked key technological hallmarks of complex societies found in other world regions, despite their observed large scale and complex, hierarchical political and economic formations. Such presumed absences are encoded in the Seshat Global History Databank, a large global comparative diachronic database recording many dimensions of human societies. Analyses derived from the current version of the Seshat database necessarily reproduce these supposed absences, as they inhere in its data ontology, structure, and registry. Nonetheless, patterns observed in the dataset provide a means for identifying processes acting on and through Andean peoples and the complex political formations they elaborated. Specifically, this paper evaluates a proposed information processing threshold model of social evolution, which suggests that social dynamics are driven first by processes related to social scale, and then by a phase of dynamics in which further scalar increases are only possible through innovations in information processing. The Andean region appears to violate this model because the Seshat database records writing and other information processing technologies as absent in the case of the Inka empire. The author argues that the dynamics of the Andean region are actually consistent with the information threshold model, but the data as constituted do not capture the relevant variables. The Inkas elaborated sophisticated information processing on par with counterparts in other world regions, but through radically distinct forms and pathways, including the Andean khipu (knotted string registries), decimal administration, and a colossal logistical and administrative infrastructural apparatus. This interwoven bundle of technologies and institutions constituted an information revolution that surpassed the information threshold and enabled explosive Inka imperial expansion, even as it produced certain vulnerabilities and fragile sovereignty.