The vast agro-urban settlements that developed in the humid tropics of Mesoamerica and Asia contained both elite civic-ceremonial spaces and sprawling metropolitan areas. Recent studies have suggested that both local autonomy and elite policies facilitated the development of these settlements; however, studies have been limited by a lack of detail in considering how, when, and why these factors contributed to the evolution of these sites. In this paper, we use a fine-grained diachronic analysis of Angkor’s landscape to identify both the state-level policies and infrastructure and bottom-up organization that spurred the growth of Angkor as the world’s most extensive pre-industrial settlement complex. This degree of diachronic detail is unique for the ancient world. We observe that Angkor’s low-density metropolitan area and higher-density civic-ceremonial center grew at different rates and independently of one another. While local historical factors contributed to these developments, we argue that future comparative studies might identify similar patterns.