With the westward move of the Wiros I have already dealt in a former chapter. Having destroyed the Tripolje culture some passed along the sandy heaths of Galicia, entering Bohemia and Hungary through the Moravian gap, and displacing the Beaker-folk who passed northwards to Jutland, Holland and the British Isles. Others passed round the south-west shores of the Euxine to the Gallipoli peninsula where they divided, one party skirting the north Ægean coast to the grassy plain of Thessaly, where they introduced Dhimini ware, and where their sudden appearance on horseback gave rise to the legends of the Centaurs. The other party crossed the Hellespont, sacked Hissarlik II. and passed on to the grass lands in the centre of Anatolia. Here they organised the eastern Alpine tribes into a great empire, and though, apparently, they adopted the language of their subjects, they introduced some of their own words and idioms, including the numerals, into that tongue, and most important of all established in the Hittite empire the worship of the Wiro deities. Such seems to have been the distribution of the Wiros about 2000 /B.C./, or a little later, and for the next 500 years we find little evidence of movement, except that the Kassites, about 1760 /B.C./ established themselves as rulers in Mesopotamia. The great split between the Indian and Iranian Aryas must have taken place about this time, causing the former to cross Afghanistan and enter the Punjab, while the latter continued to roam the steppes of Turkestan, and eventually to cross the Volga into South Russia, where they occupied the plain as far west as the foot of the Carpathians.[488] We may now for a time leave the Asiatic sections and concentrate our attention upon those Wiros who entered what we have termed the Celtic cradle. Some passed into the mountain zone, where others had arrived before them, and made themselves lords of the settled agricultural Alpine lake-villages; these were the proto-Celts. Others seem to have remained in the plain of Hungary, continuing perhaps their former nomadic life. These, who had spread into the basin of the Morava, became the Thraco-Phrygian group. Between these two, in the lower valleys of the Drave and the Save, in Croatia and perhaps in Bosnia, were a third group, who may be termed proto-Italic. It must not be taken for granted that from the time of their arrival these three groups were quite sharply separated. We have seen, however, that the division of the people of the plain and the mountain zones arose quite early, largely from the difference between their modes of life. It is probable that many dialects arose, and that by degrees some of the mountain Wiros extended to the south-east, even as far as Herzegovina, and these gradually became separated from the main body of their fellows. The main group developed Celtic dialects, and south-eastern group Italic, though both, it must be remembered, spoke Q tongues.