For over a century, specialists have debated why the worship of the Roman emperors is important for interpretation of the Revelation of John. Now, in the first book length treatment of the topic, Steven J. Friesen argues that a detailed analysis of imperial cults, as they were practiced in the region where John was active in the first century CE, allows us to understand John's radical criticism of his society's dominant values Friesen draws on hundreds of inscriptions, coins, and architecture related to the worship of the Roman emperors to develop a newly detailed description of the imperial cults. Drawing on theoretical work in the history of religions and in postcolonial studies, he demonstrates the importance of imperial cults in the evolution of Greco-Roman polytheism and in the province of Asia. He concludes that the worship of the emperors promoted a cosmology that supported Roman imperialism within the bounds of normal urban religion. The use of architecture, iconography, ritual, and myth in these cults promoted this cosmology through new definitions of meaningful time and space.