The Seljuk Empire was a medieval Turko-Persian empire, originating from the Qynyq branch of Oghuz Turks. The Seljuq Empire controlled a vast area stretching from the Hindu Kush to eastern Anatolia and from Central Asia to the Persian Gulf. From their homelands near the Aral sea, the Seljuqs advanced first into Khorasan and then into mainland Persia before eventually conquering eastern Anatolia. The Seljuq/Seljuk empire was founded by Tughril Beg (1016-1063) in 1037. Tughril was raised by his grandfather, Seljuk-Beg, who was in a high position in the Oghuz Yabgu State. Seljuk gave his name to both the Seljuk empire and the Seljuk dynasty. The Seljuqs united the fractured political scene of the eastern Islamic world and played a key role in the first and second crusades. Highly Persianized in culture and language, the Seljuqs also played an important role in the development of the Turko-Persian tradition, even exporting Persian culture to Anatolia. The settlement of Turkic tribes in the northwestern peripheral parts of the empire, for the strategic military purpose of fending off invasions from neighboring states, led to the progressive Turkicization of those areas.