A vassal state is different from a colony. The vassal state needs to pay tribute to the suzerain every year, but it has the autonomy within the country.
On the surface, this suzerain-vassal relationship seems to be a trivial and unequal relationship, and neighboring countries want to "pay tribute to China"; It was awarded by China and stamped by China.
In fact, this suzerain-vassal relationship is only a form of maintaining friendly relations between China and neighboring countries, and there is no substantive content of ruling and being ruled. Moreover, the ruler of China, as the suzerain country, treats foreigners with an indifferent attitude, that is, "you don't treat foreigners, whoever comes to you will not refuse, and those who go will not pursue them", and in principle does not interfere in the internal affairs of vassal countries.
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In ancient times, the Korean dynasty was a subordinate country of China, but it did not belong to China. Like Ryukyu Kingdom, it pays tribute to China every year.
At the end of Shang Dynasty, Shang Zhouwang's uncle Kiko led more than 5,000 people to flee because of political discord, and became a major opposition force after Wei Ziqi, whose sphere of influence is now Changbai Mountain.
After King Wu's attack was successful, he went to look for Ji Zi. Later, under the persuasion of others, he agreed to join the Zhou royal family. After the vassal enfeoffment, Ji Zi became a vassal, and the enfeoffment was in present-day Korea, bordering on Yan State in the west. History books call it "Ji's Korea". In the next 800 years, North Korea, whose surname is Ji, has always existed as a vassal state of the Zhou Dynasty.
At the end of the Qin Dynasty and the beginning of the Han Dynasty, an insurgent army retreated eastward under the leadership of Man, took the opportunity to destroy Ji North Korea, rebuild the country, and set its capital at Pingnao. History books call it "Wei's Korea", and its sphere of influence has expanded to the present Seoul area.
Nowadays, in the historians of North Korea and South Korea, these two periods are both called colonial times. During the reign of Emperor Wu of the Han Dynasty, he sent troops to destroy Wei Korea, and set up four counties in the northern part of the Korean Peninsula: Le Lang, Xuantu, Lintun and Fan Zhen. The Korean adherents of Wei moved to the south, and established the Chen country centered on Chen Han, Mahan and Yang, which is called the "Three Han" era in history (the origin of the name of North Korea today).
At the end of the Han Dynasty, due to the disintegration of the Han Dynasty, the State of Chen was also divided into Silla, Baekje and Koguryo, which is called the Three Kingdoms Period. In Tang Gaozong, Silla, with the help of the Tang Dynasty, eliminated Baekje and Koguryo one after another, unified the Korean Peninsula for the first time, and made Gyeongju its capital, which is called Silla era.
Since the Western Han Dynasty, all countries on the Korean Peninsula have been vassals of China. Until the end of the Qing Dynasty, when the Qing Dynasty was defeated in the Sino-Japanese War of 1894-1895, South Korea broke away from the suzerain-vassal relationship with the Central Plains Dynasty, and then established the "Korean Empire". 19 10 was annexed by Japan and gained independence after World War II. 1950 The Korean War broke out and the north and south split. The northern country is called Korea, and the southern country is called Korea.