East Syriac Christians, sometimes known as Nestorians, are constantly encountered in our sources on the Mongol Empire, and were clearly widespread across the medieval Middle East, Central Asia, and China. Nevertheless, they have so far received very little attention from scholars working on the Mongol Empire, and their position within the empire is very little understood. The material and epigraphic sources produced by these communities also offer a valuable and untapped perspective on Mongol rule, as seen by its subjects. In this paper I will explore these Christian communities and their sources, and ask how their perspectives can better help us understand life in the Mongol world. I will offer some broad brush strokes on the position and spread of Christians in the empire, before focusing my attention on Christians within the Chaghatai Ulus. The most neglected of the four constituent Mongol khanates, the case of the Chaghatai Ulus can demonstrate the value of these Christian sources and perspectives for wider Mongol history. I will look at the evidence of entanglement between Chaghatai elites and Central Asian Christians, and the trans-imperial connectivity witnessed by these communities. Finally I will turn to the question of later Mongol Islamisation, and show how the perspective of Christians experiencing this development offers us a fresh way of viewing this process.