The order of the pre-Qin period was five knights, namely male, male, male and male. The descendants of the sages and three uncles of the previous dynasty sealed the marquis state (only eight, Duke Guo, Yu, Duke Song, Chen, Zhu, Qi, Jiao and Ji), and the younger brother and great hero sealed the marquis state, and later sealed the earl, viscount and baron. At this time, there is no such thing as viscount. The only king is King Zhou (Zhou Wang). Until the Chu Wuwang period, Chu Wuwang, whose title was Zi Chu at that time, was dissatisfied with the fact that King Zhou only gave himself a viscount, so he took the liberty of being king and won the Central Plains in the Chu Zhuangwang period. Soon, Qin Bo and Qi Hou became kings one after another. Under the operation of Gongsun Yan, the kings of Korea, Zhao, Wei, Yan and Zhongshan were kings at the same time, and they recognized each other's thrones, which was called the king of the five countries in history.
After Qin Shihuang unified the world, he adopted the title of emperor. Abolish the feudal system of all governors and implement the county system. Since then, the five-level title system of male and female princes has been abolished, and it has been replaced by a twenty-level military title system similar to rank, with the lowest level being male scholars and the highest level being che Hou.
After the establishment of the Han Dynasty, Liu Bang practiced the policy of coexistence of counties and countries, so the county system and the enfeoffment system existed at the same time in the Han Dynasty, so the military title and the five-product title also coexisted. Han Xin, for example, was successively named King of Qi, King of Chu and King of Huaiyin. After Han Xin, Ying Bu, Zangcha and other half-surnames died, Wang Jue began to give them only to Liu Zongshi.
At the end of the Eastern Han Dynasty, just before Cao Cao was still alive, the bugle system depreciated because of long-term operation. Any old farmer in the field can be old or left-handed. So the bugle was refined, and this title alone was divided into Xianghou (Zhuge Liang named Wuxiang Hou), Tinghou (Guan Yu was named Hanshou Tinghou by Cao Cao), Shanhaiguan Hou, Shanhaiguan Hou and so on. After Cao Pi established the Wei Dynasty, he resumed the five-rank system, which lasted until the Jin Dynasty. The rebellion of eight kings in the Jin Dynasty was the rebellion of eight Sima kings.
After the Eight Kings Rebellion, the rulers were extremely weak, and the northern aliens took advantage of it. Five different nationalities successively entered the Central Plains to establish a country, which is known as the Five Chaos in history. The Eastern Jin Dynasty, which retreated to the south, was replaced by the Song Dynasty established by Emperor Wu of Song, while the Northern Wei Dynasty was established by Tuoba. The southern regime succeeded Song Qi Liang Chen successively, and the northern regime succeeded Qi Wei Zhou Sui successively, especially for the Southern and Northern Dynasties. At this time, the title system was very chaotic, and each dynasty had its own system. For example, in Chen Nan, the founding emperor Chen Baxian divided the title into four grades: prince, vassal, county king and heir king, while in the Northern Zhou Dynasty, it was only divided into two grades: county king and county king. But there is one thing in common, that is, the nobility is exclusive to the royal family, and men and women are for heroes.
Sui and Tang dynasties basically followed this system, but also refined the duke and marquis again. Dukes are divided into dukes and counties, and Marquis are divided into dukes and Marquis.
The following five generations and ten countries are not very clear.
The title system in Song Dynasty is very special, which is linked to official positions. As long as you reach the official position, you can get the title, but it is not hereditary, which leads to the situation that eunuchs can seal the county king.
Titles in Ming Dynasty are divided into imperial clan titles and meritorious service titles. From top to bottom, the titles of imperial clan are prince, county king, general of town country, general of auxiliary country, general of service country, lieutenant of town country, lieutenant of auxiliary country and lieutenant of service country, and the titles of meritorious service are divided into Duke of Hou Bo and Duke of Hou Bo. Among them, the founding father is above the public, the founding Hou is above Hou, and the founding Bo is above Bo. Except for the nine governors who guarded the north in the early Ming Dynasty (nine prisoners who guarded the frontier fortress with military power), other governors and county kings were inferior to a powerful lord protector, especially Wei Gong of Xu Da and Zhang Yu's British Duke.
The titles of the Qing Dynasty were even more complicated. First, completely abolish princes and princes. Second, there is a difference between hereditary and hereditary replacement. Hereditary replacement is also commonly known as the iron hat king. The highest level is the "prince of Heshuo hereditary system", such as the famous prince of Heshuo alcohol.
To sum up, although the baron looks nominally higher than the duke, it is not absolute. More often, the title system is another title system independent of the male system of duke and marquis, and there is no direct grade difference. No matter how meritorious the duke is, he will not become a baron, but will be awarded other honors. Even if the baron is demoted, he will not become a duke, but a variety of strange generals and captains.