公元前2世纪以前的阿富汗斯坦,西史中称其为巴克特里亚,是亚历山大东征后在中亚建立的殖民地之一,行用希腊文。公元前2世纪中,里海北岸游牧人南下,入踞巴克特里亚。据希腊地理学家斯特拉波在地理著述中之记录,南下之游牧人中,主要的一支自称为“吐火罗”。这片土地上,自此又得有“吐火罗”之名。这一事件后不久,大月氏人进入这片地区。张骞西使,入大宛(今乌兹别克斯坦费尔干纳盆地),旋又转进康居、大月氏、大夏。大夏,张骞强调,其地“在大宛东南二千馀里,妫水(阿姆河—— In Afghanistan, before the 2nd century BC, the West known as Bactria, was one of the colonies established in Central Asia by Alexander the Great after the Eastern Detrication and was written in Greek. In the 2nd century BC, the nomads north of the Caspian Sea moved to Bactràlia. According to the records of Strabo, a Greek geographer, in the geographical writings, among the nomads southward, the chief one claimed to be ”Tocharian“. This piece of land, since then have to ”spit Fire Luo“ in the name. Shortly after this incident, the Great Moon entered the area. Zhang Qian West, into Dawan (now Uzbekistan Fergana basin), spin into Kangju, big month’s, big summer. In the big summer, Zhang Qian emphasized that its place ”is more than two thousand miles south-east of Dawan, and Huangshui (Amu-