time of Alexanders invasion (326 BC) he encountered a Puru king (Paurava tribe) named Pururava ( King_Porus ). Porus had his territory between Vitasta ( Jhelum , Hydaspes) and Chadrabhaga ( Chenab , Acesines or Asikni). It however had an extension upto Vipasa ( Beas_River , Hyphasis). Porus was also known