China's territorial expansion has gone through a long historical process. The Yellow River Basin is the birthplace of Chinese civilization, but today's territory of China far exceeds the confines of the Central Plains. South China, the Yunnan-Guizhou Plateau, Northeast China, Mongolian Grassland, Western Regions and the Qinghai-Tibet Plateau all went through different historical processes before they were gradually incorporated into China's territory. The rulers of various dynasties contributed, but also experienced the pain of losing their land. The Qing dynasty made a greater contribution to the reconquest of the frontiers, but lost the northeast and northwestern regions. The reasons for territorial expansion are complex and diverse, and cannot be simply attributed to the incompetence of the Qing dynasty. The frontier issue of the Chinese nation is a complex and severe challenge that requires our in-depth study and reflection. China's territorial expansion began with the development of the Central Plains, and the Yellow River Basin became the birthplace of Chinese civilization. The agricultural civilization in the Central Plains provided the soil for the reproduction and growth of the Chinese nation. The land that nourished us came to be known as the "Central Plains". Today, China's land area has reached 9.6 million square kilometers, dozens of times that of the Central Plains. This vast land is the result of generations of Central Plains people through conquest and cultivation, and it took thousands of years to incorporate it into the Chinese territory. South China was one of the first frontiers of China to be included in the territory.
Qin Shi Huang built the Lingqu to enable the Qin army to penetrate deep into the Lingnan region. Emperor Wudi of Han abolished the states of Nanyue and Yelang, making the entire region of South China the territory of China and laying the foundation for the southern border of modern China. When the Yunnan-Guizhou Plateau gradually declined in the Central Plains, independent regimes such as Nanzhao and Dali were formed. It was not until the Yuan Dynasty established a province in Yunnan that separatist forces were eliminated and the region was fully integrated into the Central Plains. Compared with South China, territorial expansion in other directions has undergone a long historical process. Northeast China, Mongolian steppe, Western Regions, Tibet and other places were ruled by the Hu ethnic group for most of the historical period, and did not truly belong to China until the last few hundred years. Although the Yuan Dynasty had a vast territory, its rule was short-lived, and many territories were lost again. The Ming dynasty was an inward-looking dynasty with little external expansion, and despite its great maritime power, it gave up control of the sea and concentrated on the agricultural areas of the Central Plains. However, because the region south of the Yangtze River had prospered and the economic level surpassed that of the north, most of the areas that the Ming could not effectively rule were not suitable for agriculture. The Qing Dynasty made a greater contribution to the incorporation of these frontiers into its territory. Despite the invasion of the great powers at the end of the Qing Dynasty, it still maintained a territory of 9.6 million square kilometers, which was significantly larger than the Ming Dynasty.
China's maritime territory is the product of modern thinking, and the Qing Dynasty promptly asserted China's sovereignty over the South China Sea and laid the foundation for China's maritime borders. In the northeast during the Han Dynasty, only Liaodong belonged to the Central Plains regime. Until the Tang Dynasty, due to the demise of Goguryeo, the northeast became Chinese territory. Then, the northeast was again occupied by the Hu people. The Yuan and Ming dynasties once had sovereignty over the northeast, but the Qing dynasty rose here, and the entire northeast became Qing territory. It was not until the signing of the Treaty of Nebuchu with Russia that the Qing Dynasty had the concept of a border line, dividing the territory of China and Russia in the outer Xing'an Ridge. However, Russia took advantage of the decline of the late Qing Dynasty and pushed its border all the way to Heilongjiang, losing China about 1.5 million square kilometers of territory, but the northeast region remained huge. The Mongolian steppe was incorporated into the territory by the Qing Dynasty through two means: affinity and force, and only the Tang and Yuan dynasties had belonged to China before, and the Yuan Dynasty itself was established by the Mongols. After the rise of the Ming Dynasty, the Mongols still occupied this steppe, and the Ming Dynasty could not conquer it. During the Republican period, under the instigation of the Soviet Union, Outer Mongolia became independent, and only Inner Mongolia remained. But Inner Mongolia is the richest part of the Mongolian steppe, and Genghis Khan's golden family also originated in Inner Mongolia.
It is precisely because of Inner Mongolia's 1.18 million square kilometers of land that the Great Wall has become a landscape, not a border line. The Qing Dynasty contributed greatly to the management of Mongolia. The Western Regions were also areas recovered by the Qing Dynasty and renamed Xinjiang. Only the most powerful Han and Tang dynasties were able to manage the Western Regions, and other dynasties could not even achieve nominal rule, and at most could only control the Hexi Corridor. Due to the invasion of Tsarist Russia, the Qing Dynasty lost more than 500,000 square kilometers in the outer northwest, and many parts of the five Central Asian countries now belong to Xinjiang. But Xinjiang remains China's largest province, covering 1.66 million square kilometers, one-sixth of modern China. The situation on the Qinghai-Tibet Plateau was very special, and it was not until the Yuan Dynasty that it began to belong to the Central Plains regime. However, due to extremely harsh climatic conditions, the Central Plains regime has only a symbolic military presence and government agencies on the Qinghai-Tibet Plateau, especially in Tibet. The Qing Dynasty sent troops to recover the post-Tibetan region in the late 18th century, which was the largest action by the Central Plains regime to defend Tibet's sovereignty in history. After the founding of New China, the People's Liberation Army entered Tibet, carried out land reform and abolished serfdom, and finally integrated Tibet's 1.22 million square kilometers into China.
Most of the frontiers of China opened up by the Yuan Dynasty were recovered by the Qing Dynasty, and its contribution cannot be ignored. Before the middle of the Qing Dynasty, these border areas practiced a traditional policy of restraint, mainly administered by the local ethnic groups themselves, and the imperial court did not establish a perfect political institution. This outdated system creates opportunities for foreign invasion. With the invasion of Western powers, the Qing Dynasty had to improve the border management system. During this period, the Qing Dynasty suffered both the pain of losing the northeast and northwest, and the magnificent achievements of recovering Xinjiang and demarcating more than 3 million square kilometers of frontiers. Therefore, we cannot simply blame the incompetence of the Qing Dynasty, the reasons behind the loss of the land are very complex, although the Qing Dynasty only improved the frontier system after losing millions of square kilometers of land, but it should not be generalized. China's territorial expansion is a complex and multifaceted issue. It involves many factors such as history, geography, and ethnic relations. We need in-depth research and reflection to better understand the formation and development of China's national territory. Only by understanding history can we better meet today's frontier challenges.