In mid-1947, the authoritarian Right was at its absolute nadir, crushed in the pincers of liberal democracy and communism. But Francis Parker Yockey dreamed of its rebirth. First, the Right needed a Das Kapital, then a Communist Manifesto, then a militant political party. Thus Yockey withdrew to Brittas Bay, Ireland, one of the few places in Europe untouched by the most destructive war in history. There, in a blaze of inspiration, he wrote Imperium.

Drawing upon the ideas of Oswald Spengler and Carl Schmitt, Imperium offers a philosophy of history, culture, and politics, as well as a synoptic overview of the Second World War and the post-war world. Yockey argues that the destiny of Western Civilization will be realized only by the creation of a pan-European imperial order.

Although Imperium was reviled by many on the Right for its Spenglerian rejection of biological race, it was praised by such figures as Julius Evola and Revilo P. Oliver and has exercised a profound influence on the imperialist strand of the post-war European Right, including such figures as Jean Thiriart and Guillaume Faye.