Drogön Chögyal Phagpa
Genghis Khan (c. 1162 - 1227) and his immediate successors conquered nearly all of Asia and European Russia and sent armies as far as central Europe and Southeast Asia. The emperors of the Yuan dynasty (1271-1368) in the 13th and 14th century converted to Tibetan Buddhism. Kublai Khan (reign 1269-1294; established the Yuan-dynasty in 1271) invited lama Drogön Chögyal Phagpa of the Sakya school of Tibetan Buddhism to spread Buddhism throughout his realm (the second introduction of Buddhism among the Mongols). Buddhism became the "de facto" state religion of the Mongol Yuan state. In 1269, Kublai Khan commissioned Phagpa lama to design a new writing system to unify the writing systems of the multilingual empire. The 'Phags-pa script, also known as the "Square script", was based on the Tibetan script and written vertically from top was designed to write in Mongolian, Tibetan, Chinese, Uighur and Sanskrit languages and served as the official script of the empire.