Byzantine sources show clearly enough that Asia Minor, even in the 11th century, was suffering from decrease in its population. This was caused partly by the endless levies of troops, necessitated by the struggles against the Bulgarians in the Balkans, and partly by agrarian conditions in Asia Minor, of which I have yet to speak. The consequences of this systematic depopulation first became evident when the country collapsed under the inroads of Seljuks, Mongols and Ottomans; for the defensive military strength that was for a while maintained could not disguise the fact that the national strength of the Greeks was already broken when the inroads of these peoples began. Furthermore, there was no longer any means at hand to renew this strength which had been for centuries so systematically drained. On the contrary, the depopulation went on from bad to worse, and it took place in different ways according to the varying character of the three conquering peoples. The Seljuks, who were bent chiefly on gaining new pasturing grounds, seem to have drawn the Greek population closer to themselves and to have made them of some service, instead of attempting to drive them out by force. This is proven by the accounts of voluntary or forced submission to the conquerors, into which the inhabitants were driven by the unsound agrarian conditions in Asia Minor, which were characterized by an ever-growing tendency toward larger and larger estates, a tendency against which, even in the 10th century, the clear-sighted emperors had vainly enacted the strictest laws. The consequences appeared at the time of the inroads of the Seljuks; evidently with full knowledge of these conditions, they promised the oppressed peasants in the conquered regions complete freedom in return for the payment of a head tax, if they would yield to their control. Thus great masses of the Greek population went over to the Turks and were lost to Hellenism. Emperor John Comnenos, on one of his campaigns against the Seljuks of Iconium (1120), was forced first to fight bitterly with the Greeks of that region, who had either been already half Turkified, or were, at any rate, strongly Turcophile. We see, then, that at that time large intermixtures of the native Greeks (or of the Hellenized native population) with the Seljuks must have taken place, for only through such intermixture is the fact to be explained that the Anatolian population of today, both Christian and Mohammedan, instead of showing a distinct racial stamp, rather presents strongly modified features which cannot be described as either Aryan or Mongolian.[17]