The Cambridge History of India, Vol. I: Ancient India v1.c30.s1.17

v1.c30.s1.17

For about a century after the treaty of peace between Seleucus and Chandragupta, c. 305 B.C., and half a century after the foundation of the Hellenic kingdom of Bactria, c. 250 B.C., the southern limit of the Yavana dominions was marked by the Hindu Kush. This broad band of mountainous country, which separates the great river systems of the Oxus and the Indus, was thus also the political boundary between Bactria and Paropanisadae (the Kābul valley and the country north of the Kābul river now known as Laghmān, Kohistān, and Kāfiristān). The mountain barrier, although a formidable natural obstacle, has never effectually prevented intercourse between the two fertile regions which it divides. In all ages it has been traversed by migrating tribes, by military expeditions, or by peaceful traders and pilgrims. It was crossed by Alexander, from the Paropanisadae to Bactria, in fifteen days, and recrossed in eleven days¹. The routes which led from Bactria over its passes converged at a point near the present Chārīkār where Alexander had founded the city of Alexandria-under-the-Caucasus; and, so long as this strategical position could be held, invasion was impossible. But already in 206 b.c. the expedition of Antiochus the Great had shown that the way was now open; and the object lesson was not lost. Within a few years, the Bactrian king Euthydemus and the princes of his house began their triumphal career, the first stage of which was marked by the occupation of the Kābul valley.