This article argues that during the closing decades of the nineteenth century a significant group of British imperial thinkers broke with the long-standing conventions of political thought by deliberately eschewing the inspiration and intellectual authority provided by the examples of the ancient empires. While the early Victorian colonial reformers had looked to the template of Greece, and while many later Victorians compared the empire in India with the Roman empire, numerous proponents of Greater Britain (focusing on the settler colonies, and associated in particular with the movement for imperial federation) looked instead to the United States. I argue that the reason for this innovation, risky in a culture obsessed with the moral and prudential value of precedent and tradition, lies in contemporary understandings of history. Both Rome and Greece, despite their differences, were thought to demonstrate that empires were ultimately self-dissolving; as such, empires modelled on their templates were doomed to eventual failure, whether through internal decay or the peaceful independence of the colonies. Since the advocates of Greater Britain were determined to construct an enduring political community, a global Anglo-Saxon polity, they needed to escape the fate of previous empires. They tried instead to insert Greater Britain into a progressive narrative, one that did not doom them to repeat the failures of the past.