Torkmans are a branch of the Middle Asian Turks that had a nomadic life in the extended deserts of the lower region of the Seyhoon River and the Aral River from the ancient age. After the Collapse of Goog Turk Empire a group of turks that were calld Aghooz, separated of them and immigrated from Archon region to Aral and Sayir Sea. The main centers of settlement of Turkmens are: Turkmenistan, Iran, Afghanistan, Iraq, Turkey, Jordan, Syria, China, Tajikistan, Russia, and Uzbekistan. Iran is one of the main settlements of Turkmens. Iranian Turkmens live in eastern south of Caspian Sea and Turkmen Sahra. They have scattered in the Provinces of Golestan, Razavi Khorasan and North Khorasan. Their population is about 2 million people. Turkmen, Aghghola and Gonbad Ghaboos are the important cities of Turkmens in Iran. From the eleventh century, first the name of Turkmen was used as a plural name of "Turkmanan" by Iranian authors such as Gardizi and Beyhaghi then it was used in the same meaning "Aghoz" in Turky and Ghoz in Arabic and Persian. In the first of eightieth, the term of "Oghoz" was used for the first time in Turkish language on the Copings in Mongolia. Oghozes was a major part of nomadic Empire that was extended from China to border provinces of Iran, Bizans and Volga River. According of these copings, Oghozes were formed of nine tribes. Some of authors believe that Oghozes were 24 tribes. For the first time, the name of Turkmen was raised in the last of tenth century. Study on the origin and meaning of the word of Turkmen shows that Non-Muslim Oghozes called Muslim Oghozes "Turkmen". Later, the name of Turkmen was used by Oghozes. Although they didn't forgot their ancestral name but events of the second half of the tenth century and the first half of the eleventh century played an important role in the Oghorian history. These events included of the conversion to Islam and The emergence of the government of Seljuqi. In this time, Oghozes didn't have a "Khan" but they had a Yabgho (king).