"Cut five cities today, cut ten cities tomorrow, but sleep peacefully", from the Theory of the Six Kingdoms. During the Spring and Autumn Period and the Warring States Period, the princes were everywhere, the wars between countries were continuous, and in the face of powerful countries, some small countries chose to "cut the city and seek peace" in order to avoid being annexed, but often the final end was only the end of being annexed.
In addition to the Spring and Autumn Period, in the late Qing Dynasty, the Western powers forced the Qing government to sign many unequal treaties, including many land-cutting treaties, and in the land-cutting treaty, no matter which land it was, the Qing government only stipulated that it was leased for 99 years, never more than 99 years.
This has to start with the unequal treaty signed between the Qing government and Britain in 1841, after the defeat of the Opium War, the British demanded that the area south of hong Kong's Kowloon Peninsula be assigned to the British as a concession for 100 years, when the Qing government vigorously prevented it and demanded only 99 years of rent.
Even the later Shandong region signed a contract with Germany in 1999, France also 99 years, never more than 99 years, 100 years and 99 years although it seems to be only one year, but the difference can be great, at that time according to the international unwritten regulations, all areas leased for 100 years, permanently lost the sovereignty of this land.
That is to say, this land will be owned by the great powers in a hundred years, if it is only 99 years, it will definitely be returned, which the Qing government is also very aware of the plans of the Western powers, and their lease time in these 99 years is "legal", once it exceeds 99 years, it is an act of aggression.
In the past 99 years, China's national strength has gradually become stronger, and some lands have also returned in advance, but Macao and Hong Kong have returned after 99 years, in fact, before the return of Hong Kong, the United Kingdom mentioned the early return of the country with our country, but this mention of "return" is costly.
This price is that after the return, the United Kingdom retains sovereignty and the right to change the right to govern in Hong Kong, which is that after the "return" of Hong Kong, the United Kingdom still retains the existing governance model, although in theory of the return, but in fact it is still a British colony, and after 99 years, Hong Kong is the nominal return.
The reason why England made this demand was because of the Outbreak of the October Revolution in Russia, when the British working class had heard of the Russian October Revolution, they had joined it, and the new British regime was in urgent need of recognition, and England naturally set its sights on our country.
But they did not want to lose Hong Kong, so they proposed sovereignty for the right to govern, our country naturally strongly opposed, would rather wait a few more years, can not give the territory to people, the Qing government is also very clear, money can be earned again, but the territory must not be lost, they are also after difficult negotiations to set 99 years.
If the Qing government did not understand the Basic Law of International law at that time, it would have been deceived by the great powers, and it would be difficult for China's territory to return.