The Battle of Qatwan was fought in September 1141 between the Kara-Khitan Khanate and the Seljuq Empire

Great Seljuq Empire

The Great Seljuq Empire was a medieval Persianate, Turko-Persian Sunni Muslim 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...

 and its vassal-state the Kara-Khanids

Kara-Khanid Khanate

The Kara-Khanid Khanate was a confederation of Turkic tribes ruled by a dynasty known in literature as the Karakhanids or Ilek Khanids, . Both dynastic names represent titles with Kara Kağan being the most important Turkish title up till the end of the dynasty.The Khanate ruled Transoxania in...

. Following the Kara-Khanid defeat at Khujand

Khujand

Khujand , also transliterated as Khudzhand, , formerly Khodjend or Khodzhent until 1936 and Leninabad until 1991, is the second-largest city of Tajikistan. It is situated on the Syr Darya River at the mouth of the Fergana Valley...

, Mahmud summoned his overlord Ahmed Sanjar to protect Western Kara-Khanid from invasion.

Battle

On the Qatwan steppe, north of Samarkand, the battle was joined. After dividing their armies into three contingents, the Kara-Khitans forced the Seljuq center into a wadi. Faced with no way out, the Seljuq army was destroyed and Sanjar barely escaped. Among those captured at the battle were Seljuq military commanders and Sanjar's wife.

Aftermath

Yelü Dashi

Yelü Dashi

Yelü Dashi , or Yeh-Lü Ta-Shih was the founder of the Western Liao dynasty, or the Kara-Khitan Khanate....

 spent ninety days in Samarkand, accepting the loyalty of Muslim nobles and appointing Mahmud's brother Ibrahim as the new ruler of Samarkand

Samarkand

Although a Persian-speaking region, it was not united politically with Iran most of the times between the disintegration of the Seleucid Empire and the Arab conquest . In the 6th century it was within the domain of the Turkic kingdom of the Göktürks.At the start of the 8th century Samarkand came...

. However, Yelu did allow the Muslim Burhan family to continue to rule Bukhara

Bukhara

Bukhara , from the Soghdian βuxārak , is the capital of the Bukhara Province of Uzbekistan. The nation's fifth-largest city, it has a population of 263,400 . The region around Bukhara has been inhabited for at least five millennia, and the city has existed for half that time...

. After this battle, Khwarazm became a vassal state of the Kara-Khitan. In 1142, Yelü sent Erbuz to Khwarazm to pillage the province, which forced Atsiz

Atsiz

Atsïz was Khwarazm Shah from 1127 until his death. He was the son of Qutb ad-Din Muhammad.Atsïz gained his position following his father's death in 1127. During the early part of his reign he focused on securing Khwarazm against nomad attacks. In 1138 he rebelled against his suzerain, the Seljuk...

 to agree to pay 30,000 dinars annual tribute.

Legend

Stories of this battle, told during the Second Crusade

Second Crusade

The Second Crusade was the second major crusade launched from Europe. The Second Crusade was started in response to the fall of the County of Edessa the previous year to the forces of Zengi. The county had been founded during the First Crusade by Baldwin of Boulogne in 1098...

, filtered back to the Holy Land

Holy Land

The Holy Land is a term which in Judaism refers to the Kingdom of Israel as defined in the Tanakh. For Jews, the Land's identifiction of being Holy is defined in Judaism by its differentiation from other lands by virtue of the practice of Judaism often possible only in the Land of Israel...

, inspiring stories of Prester John

Prester John

The legends of Prester John were popular in Europe from the 12th through the 17th centuries, and told of a Christian patriarch and king said to rule over a Christian nation lost amidst the Muslims and pagans in the Orient. Written accounts of this kingdom are variegated collections of medieval...

.