How did Yelü Chucai change the Mongol taxation system in China?

Yelü Chucai, a statesman of Khitan extraction and an adviser to Genghis Khan and his son Ögödei, was instrumental in transforming the Mongol taxation system in China. He persuaded Ögödei to move away from indiscriminate levies and establish a rationalized taxation system that more closely resembled Chinese traditions.12

Yelü Chucai's reforms included:
* Establishing a formal bureaucracy and the Central Secretariat (Zhongshu Sheng) to centralize civilian administration.12
* Dividing the territory into provinces with administrations responsible for regularized taxation.2
* Implementing a land tax and a poll tax, payable in goods or silver.2
* Introducing a sales tax for merchants and establishing monopolies on wine, vinegar, salt, and mining products.2

These changes allowed the Mongol court's treasuries to accumulate significant wealth, though Yelü Chucai faced opposition from Mongol feudatories and nobles who preferred to exploit their own territories without centralized oversight.12