In 581 ad, Yang Jian, the father-in-law of the emperor of the Zhou Dynasty of the Northern Dynasty, seized the power of the Zhou Dynasty of the Northern Dynasty and established the Sui Dynasty. (he was called Emperor Wen of Sui Dynasty in History)
Liu Yu (known as Emperor Wu of Song Dynasty of the Southern Dynasty in History) successfully established the Song Dynasty of the Southern Dynasty（Also known as the Liu Song Dynasty） after pacifying the South and abolishing the last emperor of the Eastern Jin Dynasty.
At the end of the Western Jin Dynasty, Liu Yuan, the Hun, successfully established hanzhao (also known as Qian Zhao or Han state) and let some relatively small anti Jin forces attach to him.
After the establishment of the Western Jin Dynasty, Sima Yan (known as Emperor Wu of Jin in History) successfully reunified China.
In 220 AD, Cao Pi became emperor and established the power of Cao Wei.
In 2 ad, drought and locusts occurred in the Central Plains.
In 25 ad, Liu Xiu and his entourage decided that the time was right and decided to stand on their own as emperor. (he was known as Emperor Guangwu of the Han Dynasty in History).
In 202 BC, Liu Bang, king of the Han Dynasty, became the emperor officially, known as Emperor Gaozu of Han Dynasty in history. (the Western Han Dynasty dates from 206 BC when Liu Bang was called the king of the Han Dynasty).