In many ways, the nomads were in constant training for war. China's dynasties were continually threatened by these nomadic invaders and the success of an emperor very often rested on how effectively he dealt with them. Although Imperial China was ruled by all powerful emperors, the survival of China depended on agriculture and the vast majority of the Chinese people who worked the fields. Eventually, greed, corruption, famine, natural disasters, and nomadic invasions contributed to the fall of even the most powerful dynasties. China's geography has also determined its history.
China is a very large and varied country.
It is composed of many different climates, geographic features, and racial origins. China's natural products are largely dependant on rainfall. Wheat, millet and barley are grown in the northern provinces and rice in the southern. Hemp was the main source of textiles until the introduction of cotton in the tenth century. Since 1000 BC, mulberry orchards have been kept to raise silkworms.