Again, a century or so later, certain portions of Western society, especially the populations of North and Central Italy and the Low Countries, had outdistanced the rest in economic development and needed institutions of local self-government to give their economic vitality free play. In this case, again, Western civilization reverted to an Ancient Greek institution and revived the 'city-state'. A little later still, the rapidly growing and differentiating body of Western civilization was impelled towards territorial expansion, and sought it, like Ancient Greece in a similar period, round the shores of the Mediterranean. This mediaeval movement of expansion, which is commonly called the Crusades, but which made itself felt in Spain and Sicily and the Aegean as well as in the 'Holy Land', is a remarkable parallel to the propagation of Ancient Greek city-states round the same shores between about 750 and 600 B. C. In drifting back upon the Mediterranean, the mediaeval West was searching for new realms to conquer, but it was really captured by the romance of its ancestral home. Here, then, are three prominent features in mediaeval Western history--the Holy Roman Empire, the Flemish and Italian communes, and the Crusades--which were legacies from Ancient Greek history in the sense of being subconscious reversions to the habits of the parent society. But have these mediaeval legacies from Ancient Greece been really important constituents in our history viewed as a whole? Have they not rather been false growths which led to little or nothing? The Holy Roman Empire was never more than a mirage. The sense of unity in the modern Western world is derived not from this but from a really original institution, the early Papal Church, in which any legacy from Ancient Greece would be hard to discern. The national states of modern Europe and America are derived not from mediaeval Ghent or Bruges or Florence or Venice but from the new, though clumsy, feudal communities of mediaeval England and France. And the expansion of Western society has not followed the direction indicated by the Crusades. The false trail of the Mediterranean was practically abandoned after less than three centuries' trial. The true domain of modern Western civilization has been found in regions which Ancient Greece hardly explored: Northern Germany and Scandinavia and the British Isles, the North Sea and the Baltic, the Atlantic and the continent of America. Thus our mediaeval legacies from Ancient Greece--the subconscious reversions of childhood--are historical curiosities rather than vital links between the two civilizations. Our really important legacy from Ancient Greece was adopted with full consciousness and deliberation when we stood on the threshold of our own maturity.