A long time following the loss of Ukrainian political independence, the sad results of the geographical situation of the country continued. The constant attacks of Tatars and Turks, the millions of Ukrainian slaves in the slave-markets of the Orient, had to continue for many centuries to be the source of the oriental world, which was fast hurrying toward its fall. But soon the geographical situation of the Ukraine began to work positively too. The geographical situation, together with other natural factors, became one of the main causes for the formation of the Ukrainian Cossack organization. This is not the place to discuss at length the significance of the Cossack organization for the Ukraine; we are only emphasizing the fact that the Cossack organization alone has preserved the Ukraine from complete downfall. [215] The Cossack organization, as a product of geographical situation, has a parallel only in the familiar North American backwoodsmen, prairie hunters and pioneers who constituted the advance guard of European civilization on their continent. Yet this analogy is a very weak and incomplete one. The Zaporog Cossacks can in no way be compared either with the Volga, Don or Ural Cossacks, who were chiefly brigands, or with the Austro-Hungarian border-soldiers, who were a state organization. The Ukrainian Cossack organization represented the efforts for liberty and independence of the entire Ukrainian people, and, finally, led up to the revival of Ukrainian political life in the form of an independent hetman state. To be sure, the territory of this hetman state embraced barely one-half of the Ukraine, but it constituted a region about which a Piedmont of independence for the entire Ukraine might grow up. Since the last decades of the 18th Century, the geographical situation of the Ukraine on the threshold of two continents has been growing from an unfavorable position to one that may be described as very favorable. It was for the most part with Ukrainian forces that Russia finally destroyed the nomads of the Ukrainian steppes. This fact has been of great significance for the Ukraine. Since that time the vast, tho almost imperceptible, colonization movement of the Ukrainian people to the east, southeast and south, has been in progress. This movement extended the Ukrainian boundaries twice within a single century. For the second time, and in a peaceful way, the Ukraine reached the delta of the Danube, the Black Sea, the Caucasus and the Caspian Sea. All this is only an outcome of its geographical situation. In another situation the Ukrainians could not so easily dispose of unsettled lands. This expansion of the Ukrainian people has by no means reached its maximum, but it has surely passed its climax. To be sure, the migration of the Ukrainian [216]element to the east and south is still very large, but there are no longer so many uninhabited districts open to settlement as in former times, and the emigration in masses has had to stop.