[2] He was living in Jazira during Tekuder's reign and had to flee to Arghun in Khorasan after the execution, in 1284, of Mongol prince and viceroy of Anatolia Qonqurtai.

[3] He was given as hostage to Tekuder by Arghun as a condition of truce in June 1284 and put in orda of Todai Khatun, his step-mother.

Gaykhatu was sent in turn by Arghun to help Leo II against Güneri of Karaman in 1286, who had captured Tarsus from the Cilician Kingdom.

Gaykhatu invaded and burned his capital Karaman on 16 January 1287,[5] forcing Güneri to retreat to mountains.

Gaykhatu visited Konya on 3 January 1291, confirming appointment of his new tax officer Khwaja Nasir ud-Din and conduction of a new general census.

Meanwhile, a rebellion by Turkmen emirs started in Anatolia, Gaykhatu had to move into his former domains, appointing Shiktur Noyan as regent of the state while confirming Anbarchi (son of Möngke Temür) as viceroy of East stationed in Ray.

Gaykhatu's retribution was brutal, sending a commander of his personal keshig Tuladai to pillage Lorestan who obtained Afrasiab's submission.

[9] As a consequence, while Afrasiab was reinstated as ruler of Lorestan, his brother Ahmad was held at Ilkhanid court as hostage.

[10] Despite Konya was enforced by a brother of Masud II and Sahib Ataids, the Karamanids didn't leave until Gaykhatu's arrival at Kayseri.

After returning to Kayseri, he sent Goktai and Girai noyans to punish former supporters of Kilij Arslan IV in northern Anatolia accompanied by Seljuk armies.

Temür Yaman Jandar was granted the former Chobanid city of Kastamonu by Gaykhatu as an iqta due to this service.

He pardoned both Taghachar and Sad al-Din Zanjani, even appointing the latter to the post of vizier on 18 November 1292 while confirming his father-in-law Aq Buqa Jalair as commander-in-chief.

[13] Amassing huge amount of power and wealth in his hand, Sad al-Din became the real ruler of the Ilkhanate with personal army of 10.000, while gaining certain enemies as well.

In 1292, Gaykhatu sent a message to the Egyptian Mamluk Sultan Al-Ashraf Khalil, threatening to conquer the whole of the Levant if he didn't return Aleppo.

In response, his vizier Sad al-Din Zanjani[12] proposed the introduction of a recent Chinese invention called Jiaochao (paper money).

Gaykhatu agreed and called for Bolad, the ambassador of Kublai (Emperor Shizu) of Yuan China in Tabriz.

Soon, bazaar riots broke out, economic activities came to a standstill, and the Persian historian Rashid ud-din speaks even of "'the ruin of Basra' which ensued upon the emission of the new money".

Baydu left hastily towards to his appanage near Baghdad leaving his son Qipchak as a hostage in Gaykhatu's court.

Arriving in Tabriz, Taghachar set Qoncuqbal and Tuladai free, while Gaykhatu desperately begged for mercy.

[5] An alternative story of Gaykhatu's death claims Baydu made war on him because of his introduction of paper money and subsequently killed him in battle.

Among his beneficiaries were the Nestorian Christians, who praise him abundantly for his gifts to the Church, as apparent in the history of Mar Yahballaha III.

[20] Gaykhatu had eight consorts from different clans: In the Turkish TV series Kuruluş: Osman, he is portrayed as an antagonist by the Uzbek actor, Maruf Otajonov.