Even at that time, a thousand years ago, the geographical position of the Ukraine, on the edge of Europe and the steppe-country of Central Asia, proved itself dangerous. From the beginning of the Middle Ages on, innumerable tribes of Turkish-Tatar origin, came crowding out of the Central Asiatic steppes westward, thru the steppes of Southern Ukraine. The Ukraine had to be the first of all the countries of Europe to withstand the attack of these hordes. The first Ukrainian conqueror, Sviatoslav, who destroyed the state of the Khazars and Bulgars and defeated other weak hordes, was killed in the struggle with the Pechenegs. Volodimir the Great was forced to fight these nomads under the very walls of his capital. These wars with nomad tribes, which began before the Ukraine appeared in the arena of history, lasted from this time until the end of the 18th Century, with varying fortunes. At times the balance of power was on the side of the Ukraine, and then Ukrainian colonization advanced victoriously to the south and east as far as the Black Sea. At other times the nomads were victorious, and the eastern and southern boundaries of the Ukraine receded north and west. The great chains of fortifications and border walls erected by the Great Princes of Kiev, on the southeast borders of the Ukraine, were of no avail. At the time of the greatest extent of the Tatar attacks (15th to 16th Century) almost all the left half of the Ukraine was a wilderness, and in the right half Kiev was a border fortress. All the southern Dnieper country, the Boh country and Eastern Podolia, was at that time a sparsely-peopled borderland, and constantly exposed to the dangers of Tatar attacks. At that time [213]Ukrainian territory was confined to the Polissye, the northern part of Chernihiv, Volhynia, Western Podolia, Eastern Galicia and Podlakhia, and only small, very thinly populated border strips of the adjacent regions. These fluctuations in the boundaries of the Ukraine have no parallel in the history of Europe, and show most clearly in what difficult straits the Ukrainian nation was forced to live for centuries.