<P> Islamic methods of mathematics, astronomy, and science made their way to Africa, East Asia and Europe during the Pax Mongolica . Methods of paper - making and printing made their way from China to Europe . During the Pax Mongolica rudimentary banking systems were established, and money changing and credit extension were common, resulting in large amount of merchant wealth . </P> <P> Mongolia's central geographical position on the Asian continent was an important reason why it was able to play such a large role in the trade system . The Mongol army was easily able to assert strong rule throughout most of the empire . The military ensured that supply lines and trade routes flowed smoothly; permanent garrisons were established along trade routes to protect the travellers on these routes . Complex local systems of taxation and extortion that were prevalent before Mongol rule were abolished to ensure the smooth flow of merchants and trade through the empire . A system of weights - and - measures was also standardised . To make the voyage on the trade routes less harrowing, the Mongols went as far as to plant trees along the roads to shade the merchants and travellers in the summer months; stone pillars were used to mark the roads where trees could not grow . </P> <P> The Mongols sought alliances with other nations and societies to ensure the flow of trade through the empire . The Mongol army was also used to reshape and streamline the flow of trade through the continent by destroying cities on the less - important or more inaccessible routes . The Mongol military was mostly made up of cavalrymen . This allowed the military to move swiftly and easily over large distances . </P> <P> The code of Mongol law, known as the Yassa ("Great Law"), decreed strict rules and punishments in many areas of the Mongolian Empire's society, especially those areas concerning trade and commerce . The Yassa helped suppress the traditional causes of tribal feuding and war, thus helping to ensure a peaceful trading and travelling environment; theft and animal rustling were outlawed, and the Mongol Empire under Genghis Khan even established a massive lost - and - found system . Harsh penalties including a retribution of nine times the original value of stolen goods helped deter theft on Mongol roads . The Yassa also decreed complete religious freedom, ensuring that Buddhists, Muslims, Christians, etc., were all allowed to travel freely throughout the empire; religious leaders were also exempted from taxation, as were doctors, lawyers, undertakers, teachers, and scholars . The Yassa did allow for flexibility and it usually adapted, absorbed, or built upon legal systems in remote parts of the empire, thus maintaining a level of openness to various societies and ensuring peace and stability . </P>

What did the pax mongolica facilitate and what were the methods they used