Analysis of information sources in references of the Wikipedia article "로저 베이컨" in Korean language version.
Europeans were prompted by all this to take a closer interest in happenings far to the east. Four years after the invasion of 1241, the pope sent an ambassador to the Great Khan's capital in Mongolia. Other travellers followed later, of whom the most interesting was William of Rubruck (or Ruysbroek). He returned in 1257, and in the following year there are reports of experiments with gunpowder and rockets at Cologne. Then a friend of William of Rubruck, Roger Bacon, gave the first account of gunpowder and its use in fireworks to be written in Europe. A form of gunpowder had been known in China since before AD 900, and as mentioned earlier...Much of this knowledge had reached the Islamic countries by then, and the saltpetre used in making gunpowder there was sometimes referred to, significantly, as 'Chinese snow'.
