The collapse of the Mauryan rule in 187 BCE paved the way for the emergence of several powers in the Indian subcontinent. The period from the decline of the Mauryas to the rise of the Guptas (2nd century BCE to 3rd century CE) is known in Indian history as the post – Mauryan period. The Indo-Greek Kingdom, or Graeco-Indian Kingdom, also known historically as the Yavana Kingdom, was a Hellenistic-era Greek kingdom covering various parts of Afghanistan, the northwest regions of the Indian subcontinent, (all of present Pakistan), and a small part of Iran; from 180 B.C.E. to around 10 C.E. The kingdom began when the Greco-Bactrian king Demetrius invaded India in 180 B.C.E., ultimately creating an entity which seceded from the powerful Greco-Bactrian Kingdom cantered in Bactria. Bactria or Bactriana, was an ancient region in Central Asia. Alexander also had established in neighboring Bactria several cities (Ai-Khanoum, Begram) and an administration that lasted more than two centuries under the Seleucids and the Greco-Bactrians, all the time in direct contact with Indian territory. In India, the overthrow of Maurya Dynasty occurred around 185 B.C.E. The book concentrates mainly on post mauryan history.