书名页 第二篇 军 事 其骑射，则孩时绳束以板，络之马上，随母出入；三岁索维之鞍，俾手有所执射，从众驰骋；四五岁挟小弓、短矢；及其长也，四时业田猎，凡其奔骤也，跂立而不坐，故力在跗者八九，而在髀者一二。
十三世纪是属于蒙古帝国的世纪，蒙古铁骑一路从东亚打到欧洲，灭亡无数的国家，至今各地都有关于蒙古帝国的征战记忆，由于蒙古铁骑的勇猛，很多国家都只能短暂抵御蒙古铁骑的进攻，大部分都坚持不了几个月甚至几年的时间就被攻破了。
Climate: the Mongols and their horses were highly adapted to the dry and cold climate of the steppe and Siberian forests. Heat was tolerable for them， but humidity and wetness were far more troublesome. When the Mongols invaded southern Song，they suffered severely from diseases like dysentery， cholera， and malaria， as well as simply from the heat. Even the Northern Chinese had significant health problems fighting in the South under various Chinese dynasties.
公元1265年，经过长达五年的战争，忽必烈终于消灭阿里不哥，成为蒙古蒙古帝国至高无上的大汗。刘整给忽必烈的灭宋建议是:从中路突破汉水重镇襄阳，然后从汉水进入长江，攻取江南重镇鄂州，再然后顺江东下，一鼓作气平定江南。
