The Seljuk dynasty is a Turkish ethnic group that originated from the Ghuzz tribe. Its name is derived from their ancestor, Seljuk ibn Tuqaq (Dukak). Their original territory was located in the northern part of the Caspian Sea and the Aral Sea, and they embraced Islam at the end of the fourth century AH/10th century AD with a tendency towards the Sunni sect. The growth of the Seljuk Dynasty was driven by the political conditions in Transoxiana. At that time, there was a political competition between the Samanid dynasty and the Khani dynasty, where the Seljuks were more inclined to support the Samanid dynasty. After the Samanid dynasty was 250 defeated by the Ghaznavid dynasty, the Seljuks decided to become independent. Thugrul announced the establishment of the Seljuk dynasty. In the year 432 H/1040 AD, this dynasty was recognized by the Abbasid caliph in Baghdad. Under the leadership of Thugrul Bek, in 1055 AD, the Seljuk dynasty entered Baghdad, replacing the Buyid dynasty. Previously, Thugrul successfully captured Marwa and Naisabur from the Ghaznavids, and took over Balkh, Jurjan, Tabaristan, Khawarizm, Ray, and Isfahan. That year, Thugrul Bek was also given the title by the Abbasid caliph of Rukh al-Daulah Yamin Amir al-Muminin. Although Baghdad could be conquered, it was not made the center of government. Thugrul Bek preferred Naisabur and then Ray as the administrative center. The previous dynasties that had been separated now recognized the significance of Baghdad after it was conquered by the Seljuks. They even collaborated for the stability and security of the Abbasid.