Seljukids arrive in a Moslem world in full distress. There are three rival Caliphs (Umayyad in Spain, Fatimid in Cairo and Abbasid in Baghdad). A multitude of autonomous principalities and a central capacity which does not hold any more reality of the capacity since the arrival of Bouyids in 1048. However, the decline relates to the cultural plan.
They will reconstitute partially a unit of the Moslem world, except for Fatimids, during a short period which extends from 1055 with 1092.
Seljuks (or Seljukids), from which the name is drawn from the eponym ancestor, is a Turkish tribal clan pertaining to the confederation of Oghuz. They are estimated noble, from where the title of Khan. Their father founder is Duqaq. Living as nomads in the east of Transoxiane, they are gradually thorough towards the west by rival groups. Their walk leads them to the limits of the Volga where the State of Khazars is, of the Turks sedentarized and converted with the Judaism. Seljuks, of shamanist religion, are diverted towards the south and approach the Abbasid Empire. They start to settle, from 960, on banks of Syr Daria in and around the town of Jand.
The names carried by some of them let suppose conversions with the Judaism and Nestorian Christianity.
The conquest of the Abbasid empire by Seljukids will be done in several successive stages. They penetrate initially in Transoxiane where are installed Samanids, a Persian and Moslem dynasty Persian, and Karakhamids de Bukhara, of Turkish origin and placed under the authority of Ghaznavids of Afghanistan. The political balance in Transoxiane is broken. Seljukids are combined initially with Samanids against Karakhamids which is overcome in 1003 then reverse alliances in 1020 to be turned over against Samanids. Latter, they disappear from Transoxiane.
Seljukids leave the area and penetrate in Khurasan where they run up against Ghaznavids before negotiating with them the authorization to establish a few thousands of them on this ground. Received in Samarqand by Mahmud of Ghazna, Arslan, the chief of Seljukids is stopped and transferred in India where he dies in 1032.
The disappearance of Arslan starts a dynastic war of succession from which Karakhamids profit to drive out Ghaznavids.
The new Seldjukid chief, Toghni Khan, crushes Ghaznavids at Merv in 1035 in Khurasan. Three years later, Toghni Beg seizes Nichapur, the capital of the province. The victory of Dandanghan in 1040 signs the final influence of Seljukids in the Khurasan where they found a tribal system of administration consisting in distributing the capacity between the various branches of the clan placed under the authority of Toghni Beg which takes the title of Sultan. From now on, Seljukids are posed at the same time as defenders Moslem faith of Sunnite rite which they embraced and in potential predator of Abbasids.
The catch of Ispahan in 1050 opens the road to Baghdad.
In the Abbasid capital the Caliph is placed under the control of Persan Bouyids. The Caliph decides to ask for the protection of Seljukids.
New convert enters to Baghdad in 1055, during the month of Ramadan. According to the rule, Toghni Beg makes allegiance (Bay'At) with the Caliph in order to be ensured of legitimacy necessary to exert the power. The Caliph marries a niece of his new guard who asks, in compensation, for the hand of the daughter of the Caliph. He refuses. Toghni Beg marries of force the girl but she dies in 1063 without to have had of child. His nephews will succeed to him.
Alp Arslan takes the reins of the capacity which is organized according to the clannish system. This fragmentation of the capacity constitutes a major weakness of the empire. Dissidences multiply. Moreover, new groups of Turkish origin arrive to the north of Khurasan and make weigh a threat. The principal group is that of Turcoman or Turkmen. Alp Arslan tries to divert them towards the borders of the Byzantine empire, in Azerbaijan where live Christian Armenians monophysits hostile with Byzance. Turkmen agree to be turned against the Byzantines. The attraction of the spoils completes to convince them. They go gradually settle and to constitute what will become later Turkey. They settle in Konya in 1068.
Alp Arslan, whose capital is Ispahan, did not forget the commitment entered into to the Caliph to engage the fight against Fatimids of Cairo. He seizes Aleppo in 1069 but the seldjukid army is attacked on its backs by the Byzantines led by Roman Diogenes which has just seized the power with Byzance.
The battle takes place at Manazguid (or Manzikert) in 1071. The Byzantines are demolished. Roman Diogenes is captured. Seljukids give up continuing their walk towards Egypt. The arrival of Francs will constitute a barrier between the Fatimid empire and Seljukids.
In 1072 Malik Shah succeeds Alp Arslan. The safety of the empire implies the control and the control of Syria. With Turcoman allies he seizes Damascus where it places a “beg” named Atziz into 1076 which, rather quickly, will try to take its autonomy. Tutush, a brother of Malik Shah seizes the power in Damascus in 1078. His victory over a rival prince, Suleiman, in front of Aleppo in 1087, ensures his control of Syria.
In 1092, vizier Nizam Al Mulk then Malik Shah are assassinated. Some allot these assassinations to Ismaelians of Alamut, others with one of the wives of Malik. These deaths open a crisis of succession. Seven applicants are on the rows of which Tutush and four wire of the late one. The empire bursts in a federation of independent principalities. The princes are gradually dispossessed of the reality of the capacity by strong men who take the title of atabeg.
In 1104, a atabeg melts a dynasty, the Burids, which will control until 1154.
In the same way, Zengui melts the dynasty of Zenguids in Aleppo.
In spite of its dynastic instability, the seldjukid capacity invested to the legitimacy of caliphate succeeded in maintaining and reinforcing overall the Abbasid and Sunnite empire with the power of the army. However the system of the “iqta” intended to finance this powerful institution by the means of land tax concessions entrusted to the military chiefs caused to reduce the resources of the central capacity and to weaken it. This situation resembles the feudality in Occident.
The wars then the victories against the Europeans Christians, in addition, will support a progressive slip of the Arab culture towards the West, from Baghdad to Cairo.