Özbeg Khan

Giyasuddin Muhammad Uzbek Khan, better known as Uzbeg or Özbeg (1282–1341), was Khan of the Golden Horde from 1313 to 1341. He was the longest-reigning khan, under whose rule the state reached its zenith. He was succeeded by his son Tini Beg. He was the son of Toghrilcha and grandson of Mengu-Timur, who had been khan of the Golden Horde from 1266 to 1280.

Öz Beg was born in 1282. His father Togrilcha was one of the Genghisid princes that overthrew Tode-Mengu (r. 1280–1287). Later, he was executed by his brother Toqta (r. 1291–1312). Toqta took Togrilcha's widow for wife and sent his son Öz Beg to exile in a distant region of the Golden Horde: either Khorazm or the country of Circassians.

Converted to Islam by Ibn Abdul Hamid, a Sunni Sufi Bukharan sayyid and sheikh of the Yasavi order, Öz Beg assumed the throne upon the death of his uncle Toqta in January 1313 with the help of the former Khans' vizier Temur Qutlugh and of Bulaghan (or Bayalun) khatun. At his conversion, he officially took the name Ghiyāth al-Dīn Muhammad. His conversion is also mentioned in Russian chronicles, but without any detailed information; the standard entry notes that the khan Toqta died in the year 6821 (1313) and the new khan Öz Beg took the throne and "became a Muslim" (obesermenilsia). Öz Beg may have converted in order to secure support from the Muslim begs.

At first, many Mongol nobles were against him due to fears that they would be forced to adopt Islamic law. As a result, they organized a plot to kill the new khan. Öz Beg discovered the plot and crushed the rebels. Öz Beg determinedly spread Islam among the Golden Horde and allowed missionary activities to expand in the surrounding regions. Öz Beg found out that his competitor was backed by the envoys of the Great Khan Ayurbarwada Buyantu and this fact helped deteriorate his relationship with the Yuan dynasty. The last of his rebellious relatives was shamanist Ilbasan of the eastern half of the Golden Horde, who was murdered in 1320. Öz Beg installed the Muslim Mubarak Khwaja as a replacement to the throne of the White Horde, but he discouraged their independence. In the long run, Islam enabled him to eliminate inter-factional struggles in the Horde and to stabilize state institutions. Russian scholar Lev Gumilev wrote that in this manner was Öz Beg able to turn the khanate into a sultanate.

Despite his strong commitment to Islam, Öz Beg allowed the Russian Church and other religious minorities to feel free from oppression, and he confirmed Mengu-Timur's decree to give Russian clergy a tax exemption. Öz Beg was very tolerant of Christians as exemplified by a letter of thanks he received from Pope John XXII, in which the Christian leader thanked Öz Beg for his kind treatment of Christians. Öz Beg also permitted Christians to operate in the regions bordering the Black Sea. Öz Beg had sent a letter to Metropolitan Peter which stated:

By the will and power, the greatness and most high! Let no man insult the metropolitan church of which Peter is head, or his service or his churchman; let no man seize their property, goods or people, let no man meddle in the affairs of the church...Their laws, their churches and monasteries and chapels shall be respected; whoever condemns or blames this religion, shall not be allowed to excuse himself under any pretext, but shall be punished with death.

The khan also granted tax exemption to the Franciscan missionaries in the Golden Horde, following the Mongolian fiscal tradition.

Öz Beg maintained one of the largest armies in the world, which exceeded 300,000 warriors. He employed his military clout to conduct campaigns against the Ilkhanate in Azerbaijan in 1319, 1325 and 1335. Ilkhanid commander Chupan repulsed one Öz Beg's first two attempts and even invaded deep into the Jochid Ulus in 1325. Öz Beg found an ally against the Ilkhanids in Mamluk Egypt; indeed, one of Cairo's squares was named after him. The Khan had the daughter of previous Khan's sister, Princess Tulunbuya, married to a Mamluk sultan, but she died in a few years. The khan instructed his merchants to lend 27,000 dinars to the Mamluk ambassador in order to finance the feast for the bride at Sarai. Soon after Öz Beg was disappointed with the Mamluk sultan's divorce with Tulunbuya and indecisiveness regarding the joint invasion of Ilkhanate. In 1323, a peace treaty was signed between Egypt and the Ilkhanate. This situation nullified the alliance and the Mamluks refused to invade the Ilkhanate. Öz Beg's next incursion coincided with Abu Said's death. However, the weather turned bad and the new Ilkhan Arpa Ke'un came with a large force; Öz Beg's army was forced to withdraw.