In the spring of 328 Alexander crossed the Hindu Kush into Bactria and followed the retreat of Bessus across the Oxus and into Sogdiana (Bokhara).
The Taurus and Iran, (8) Cilicia, (9) Syria, (io) Mesopotamia, (11) Babylonia, (12) Susiana; in Africa, (13) Egypt; in Iran, (4) Persis, (15) Media, (16) Parthia and Hyrcania, (17) Bactria and Sogdiana, (18) Areia and Drangiana, (19) Carmania, (20) Arachosia and Gedrosia; lastly the Indian provinces, (21) the Paropanisidae (the Kabul valley), and (22) the province assigned to Pithon, the son of Agenor, upon the Indus (J.
The eastern provinces of Iran went in 240 or thereabouts, when the Greek Diodotus made himself an independent king in Bactria(q.v.) and Sogdiana, and Tiridates, brother of Arsaces, a " Scythian " chieftain, conquered Parthia (so Arrian, but see Parthia).
The name first appears in the list of primitive Zoroastrian settlements contained in the Vendidad Sade, where, however, like most of the names in the same list, - such as Sughudu (Sogdiana), Mouru (Mer y or Margus), Haraquiti (Arachotus or Arghand-ab), Haetumant (Etymander or Helmund), and Ragha (or Argha-stan),--it seems to apply to the river or river-basin, which was the special centre of population.
After the conquests of Alexander the Great Sogdiana formed part of the empire of the Seleucidae, and shared the fortunes of the rather better-known Bactria.