The Outline of History, subtitled either "The Whole Story of Man" or "Being a Plain History of Life and Mankind", is a work by H. G. Wells that first appeared in an illustrated version of 24 fortnightly installments beginning on 22 Nvember 1919 and was published as a single volume in 1920. It sold more than two million copies, was translated into many languages, and had a considerable impact on the teaching of history in institutions of higher education. Wells modelled the Outline on the Encyclopédie of Denis Diderot.
Wells was uncertain whether to place "the beginnings of settled communities living in towns" in Mesopotamia or Egypt. He was equally unsure whether to consider the development of civilisation something that arose from "the widely diffused Heliolithic Neolithic culture" or something that arose separately. But between the nomadic cultures that originated in the Neolithic Age and the settled civilisations to the south, he discerned that "for many thousands of years there has been an almost rhythmic recurrence of conquest of the civilizations by the nomads."
According to Wells, this dialectical antagonism reflected not only a struggle for power and resources, but a conflict of values. "Civilization, as this outline has shown, arose as a community of obedience, and was essentially a community of obedience. But . . . here was a continual influx of masterful will from the forests, parklands, and steppes. The human spirit had at last rebelled altogether against the blind obedience of the common life; it was seeking . . . to achieve a new and better sort of civilization that should also be a community of will." Wells regarded the democratic movements of modernity as an aspect of this movement.