The Upper Satrapies () is a collective term used in the Hellenistic period to refer to the eastern, Iranian-populated, provinces ("satrapies") of the empire of Alexander the Great, especially during the Wars of the Diadochi and the subsequent Seleucid Empire. At times, it also corresponded to a single super-province, under a strategos "in charge of the upper satrapies" (). Extent The Upper Satrapies comprised the entire eastern half of the territories conquered by Alexander: typically everything east of the River Tigris, from the Zagros Mountains in the west to the borders of India in the southeast and Central Asia in the northeast, including the provinces of Media, Persis, Carmania, Drangiane, Hyrcania, Parthia, Margiane, Aria, Baktria, and Sogdiane. The area initially also included the easternmost conquests of Alexander in India and modern-day Afghanistan and Pakistan (the Paropamisadai, Arachosia, and Gedrosia), but these were definitively lost to Chandragupta Maurya in 303 BC, after his treaty with Seleucus I Nicator. History Possible Achaemenid antecedents It is possible that the concept and province of the "Upper Satrapies" was created already during the late Achaemenid Empire, where superior military commands covering several satrapies are attested for Asia Minor at least, with scholars hypothesizing also the existence of similar arrangements for the Armenian, Syriac-Babylonian and eastern satrapies. The evidence for the eastern satrapies is based on a statement by Diodorus of Sicily that Artaxerxes III entrusted the Upper Satrapies to Bagoas, but this may be an anachronism, and no other piece of evidence survives indicating any continuity between the Achaemenid and Hellenistic periods in this regard. Establishment under the Diadochi The first mention of the "Upper Satrapies" comes from 316 BC, when Peithon was named strategos of Media and of the Upper Satrapies as well by Antigonos I Monophthalmos. Peithon, the satrap of Media, had been elected by the army assembly in 323 BC to supervise the suppression of a revolt by mercenaries in the eastern satrapies, and had received some plenipotentiary powers over the local satraps. Although likely not envisioned at the outset as an overarching military command as it later became, Peithon appears to have attempted to gradually impose just such an authority over the local satraps, which led to the latter banding together against him and evicting him in 317 BC. It was in this context that Antigonos recognized his claims to win him over, although soon after, Antigonos had Peithon arrested and