Considerable attention has been paid to the ideas of critics of the British Empire in the period of its most rapid expansion and rather less to the views of those who supported it strongly. This article investigates the arguments of what are called “ultra-imperialists”, showing how they used the language of character, stiffened by elements from earlier languages of virtue, to justify the possession of empire. They argued that character had been critical in making Britain an imperial power and also claimed that, without the stimulus to action and duty provided by the defence and the governance of empire, character would atrophy, and the nation would suffer catastrophic and irreversible decline. The article ends by comparing the “ultra” position with that of, firstly, the larger body of more pragmatic supporters of empire and, secondly, the small group of radical anti-imperialists who feared that empire was destructive of character.