The expansion of China's historical territorial boundaries is more in line with the social production capacity of the time. Simply put, there must be land suitable for reclamation, or areas with operational value, which will become the target area for the expansion of the territory of the feudal dynasty.
From the changes in China's territory since ancient times, we will find that since the origin of Chinese civilization in the Central Plains, our ancestors have constantly searched for the most suitable land for survival. With the increasing population of the Chinese ethnic group, our demand for land has also expanded. The Qin Dynasty Opened Up the Lingnan Region for the Development of the Chinese Nation Taking the earliest feudal unification dynasty, the Qin Dynasty, when Qin Shi Huang unified the Six Kingdoms, he was not satisfied with the original territorial areas of the Six Kingdoms, but his vision was farther, and he saw the Baiyue and Southern Yue regions in the far south.
To this end, he did not hesitate to build a spiritual canal to connect the Yangtze River with the Pearl River, and sent 500,000 Qin troops to explore and conquer this relatively barbaric and backward area, just because these places may become the second tianfu of the Qin Dynasty in the future. The Han Dynasty opened up the Western Regions for the Silk Road And the successor of the Qin Dynasty, the Han Dynasty, not only inherited the new territory developed by the Qin State in the southeast, but also began to advance to the western region in the northwest direction due to the emergence and development of the overland Silk Road, during which although it stopped with the Xiongnu for nearly a hundred years, but in the face of the huge economic and military value of the Western Silk Road, the Han Dynasty finally gained control of the Hexi Corridor and the Western Regions at any cost, and established the Western Regions Protectorate to protect the economic interests of the Han Dynasty in this region.
At the same time, due to the relatively warm climatic conditions at this time, the reclaimable areas of the Han Dynasty have also been greatly increased, which is why we can see on the map of the Han Dynasty that the territory of the Han Dynasty has expanded to liaodong and most of the Korean Peninsula. After that, our military power has also expanded to the more remote northern cold zone and the southern hot Indochina Peninsula region, but because these areas are synonymous with bitter cold and miasma for the Central Plains Dynasty accustomed to temperate areas, not only is it difficult to develop, but also the fatality rate of harsh environments and diseases is extremely high, and for the feudal dynasty that does not have modern logistics support and medical system, it is obviously an area that cannot be continuously developed, and it is naturally impossible to produce value. In this way, it will not attract the goal of feudal dynasties to build and expand their territories to these lands. The Tang Dynasty's enlightened ethnic policy adopted mandated rule
The Battle of Hengru in Central Asia, which has been discussed by posterity in history, was actually mainly a war of interests for the Silk Road. The expansion of the territory of the Yuan Dynasty mainly depends on the mode of raising war with war, and the real expansion of the territory to the limit is actually the Yuan Dynasty, but the expansion of the Yuan Dynasty stems more from their mode of war that does not require too much logistical support, that is, the mode of one man and three horses, and the mode of raising war with war.
This was almost impossible for other feudal dynasties, and when the mongol conquests stopped, the shortcomings of being too vast but unable to keep up with the management organization began to manifest themselves, and the huge Mongol Empire split into five states.
During the Ming and Qing dynasties, the territory expanded, benefiting from the introduction of high-yield species The Ming Dynasty, for the sake of these realities, most of these areas that did not have much value were set up as countries without conquest.
The Qing Dynasty, on the other hand, benefited from the introduction of high-yielding crops from overseas in the late Ming Dynasty, such as potatoes, sweet potatoes, and corn, which could be planted in large quantities in the north, solved logistical problems, and expanded the territory to the extent we see now. So, in general, the expansion of The territory of China's feudal dynasties often matches the current social productivity or economic value. If there is no value, naturally no one will go to open up, just like Europe in the age of great navigation, if the output of the colony is not valuable, will they build a colony? It's that simple!