The Graeco-Roman world saw a civilization far more brilliant, far more varied and intense, than any that had gone before it, and one that affected a far larger share of the world’s surface.  For the first time there began to be something which at least foreshadowed a “world movement” in the sense that it affected a considerable portion of the world’s surface and that it represented what was incomparably the most important of all that was happening in world history at the time.  In breadth and depth the field of intellectual interest had greatly broadened at the same time that the physical area affected by the civilization had similarly extended.  Instead of a civilization affecting only one river valley or one nook of the Mediterranean, there was a civilization which directly or indirectly influenced mankind from the Desert of Sahara to the Baltic, from the Atlantic Ocean to the westernmost mountain chains that spring from the Himalayas.  Throughout most of this region there began to work certain influences which, though with widely varying intensity, did nevertheless tend to affect a large portion of mankind.  In many of the forms of science, in almost all the forms of art, there was great activity.  In addition to great soldiers there were great administrators and statesmen whose concern was with the fundamental questions of social and civil life.  Nothing like the width and variety of intellectual achievement and understanding had ever before been known; and for the first time we come across great intellectual leaders, great philosophers and writers, whose works are a part of all that is highest in modern thought, whose writings are as alive to-day as when they were first issued; and there were others of even more daring and original temper, a philosopher like Democritus, a poet like Lucretius, whose minds leaped ahead through the centuries and saw what none of their contemporaries saw, but who were so hampered by their surroundings that it was physically impossible for them to leave to the later world much concrete addition to knowledge.  The civilization was one of comparatively rapid change, viewed by the standard of Babylon and Memphis.  There was incessant movement; and, moreover, the whole system went down with a crash to seeming destruction after a period short compared with that covered by the reigns of a score of Egyptian dynasties, or with the time that elapsed between a Babylonian defeat by Elam and a war sixteen centuries later which fully avenged it.

This civilization flourished with brilliant splendor.  Then it fell.  In its northern seats it was overwhelmed by a wave of barbarism from among those half-savage peoples from whom you and I, my hearers, trace our descent.  In the south and east it was destroyed later, but far more thoroughly, by invaders of an utterly different type.  Both conquests were of great importance; but it was the northern conquest which in its ultimate effects was of by far the greatest importance.