Contrary to popular belief, the arrival of the Arab Islamic armies in Persia and Central Asia did not lead to the eradication of Christianity. Mingana records that as late as the eleventh century, the Metropolitan of Merv reported "two hundred thousand Turks and Mongols had embraced Christianity," including the entire Kerait people group. Nor was Christianity exterminated by the Mongol conquests of the 13th century, as is sometimes claimed. Christianity, in fact, was alive and well during the Mongol period. Uighur and other Turco-Mongolian tribes took part in the Mongol conquests, travelling to war accompanied by Nestorian priests and mobile chapels mounted on carts. Two of Gengiz Khan's sons had Christian wives. Hulugu, founder of the Ilkhamid Empire, is reported to have even considered baptism. Under Hulugu, Christianity experienced a short renaissance, for his queen, Dokuz, was a zealous believer.
When Marco Polo and other Papal emissaries arrived at the Mongol court in the 13th century, they were astonished to find multi-ethnic groups of Christians, including among the Mongolians, Uighurs, Naimans, Keraits and Merkites. The death blow to Nestorian Christianity in Central Asia was delivered by Timur (Tamarlane) in the 14th century. He rigorously persecuted the church, destroyed most of their buildings, and either forcibly converted the population to his particular brand of Islam--a mixture of Sufi and Shamanistic mysticism--or exterminated the indigenous communities along with hundreds of thousands of other peoples who stood in the way of his ambition of world conquest.