According to numerous Puranas, the military corporations of the Shakas, Yavanas, Kambojas, Pahlavas and Paradas, known as "five hordes" (pānca-ganah), had militarily supported the Haihaya and Talajunga Kshatriyas in depriving Ikshvaku king Bahu (the 7th king in descent from Harishchandra), of his Ayodhya kingdom.
King Sagara had divested the Paradas and other members of the Panca-ganah of their noble Kshatriyahood and demoted them to the barbaric caste of Mlechchas, due to their non-observance of sacred Brahmanical codes and neglect of the priestly class.
Like the Shakas, Pahlavas, Kambojas, Paradas, a section of the Rishikas had also migrated to west/south-west India prior to Christian era.