Final answer:
The Mongols used a mix of conscription, employment of skilled foreign workers, and infrastructure development to recruit and maintain a labor force. This enabled them to construct a well-coordinated army and support trade and communication, leading to the Pax Mongolica.
Step-by-step explanation:
The Mongols recruited people to work for them through a number of methods, including conscription, the employment of foreign expertise, and the provisioning of benefits to merchants. All capable men up to the age of seventy were conscripted into the Mongol army. However, this highly mobile and coordinated military force never exceeded 100,000 men. The Mongols also employed skilled individuals such as Chinese engineers to teach them the construction of siege engines like catapults, trebuchets, and battering rams.
Beyond military recruitment, the Mongols improved infrastructure, such as building bridges essential for mobilizing armies and aiding merchant travel, and maintained a well-organized system of roads and relay stations known as örtöö, which supported trade and communication. In this system, local populations were often required to staff and maintain these stations as a form of tax payment. Through such infrastructure and policies, the Mongols integrated various aspects of their empire, which helped them enforce their rule and facilitate the Pax Mongolica, a period of relative peace and stability that encouraged the exchange of goods and ideas across Eurasia.