The great khan Mungge (Mengu) had sent a great army under the command of his brother, Hulagu to Iran in the year of 1253. Hulagu passed over the River Oxus in the year of 1256 and received small local beys in Iran and Caucasus in order to subdue them under his dominion. The chief of Ismaili supporters, Ruknettin who was the possessor of a great force and influence was among these last visitors. Since Rukneddin was not accepted among the submissive persons, he ran away to the castle of Alamut and tried to oppose him. However, he could not be successful and he and his supporters in Iran were annihilated within a short period. Hulagu had planned to establish a big state in this region in his capacity as the vassal of the great khan. Pursuant to the completion of the invasion of Iran, he captured Baghdad in the beginning of the year 1258. The caliph Mustasim had delayed in the recognition of the dominion of Hulagu and he did not have adequate forces to resist to him, either. Then, he was killed with the members of his family. However, some of the members of the Caliph's family could only save their lives through their flight to Egypt. Two persons among these people were declared as caliphs respectively by Sultan Baybars in the years of 1260 and 1261 and this family continued the so-called caliphate until the conquest of Egypt by the Ottoman State. Pursuant to the capture of Baghdad, the Syrian Bey Principalities were submissive under the protection of Hulagu. However, the Turkish forces in Egypt had replied to the demand of Hulagu for submission with a raid towards Palestine. They defeated the army of Hulagu in Ayn Calut near Nabulus in the year of 1260.
The successors of Hulagu were involved in the struggles against Turkestan and Golden Horde and they tried to collaborate with the European States against the Egypt Turkish State. In the period of Ahmed who adopted the religion of Islam (1282-1284), Islam started to get disseminated among the main forces of the Ilhanli State. Gazan Khan (1295-1304) was enthroned through the supports of the Muslims and he adopted the religion of Islam and undertook the name of Mehmed. In his period, the rest of the people of the Ilhanli State had become Muslims. The organisation of the Ilhanli State did not live long. The greedy struggles that burst out since the period of Ebu Said Bahadir Khan (1316-1335) increased gradually pursuant to his death and undermined the foundation of the state. The force and authorities in the country were under the dominion of two dynasties such as Emir Çoban Sons in Azerbaijan and the dynasty with the founder of Sheikh Hasan in Baghdad. The weakening of central power led to the declaration of the independencies of several local beys that had been submissive to them in the past.