After the "Eight Kings Rebellion" at the end of the Western Jin Dynasty, five princes of Sima family, namely, the king of Langya, the king of Nantang, the king of Pengcheng, the king of Runan and the king of Xiyang, crossed the Yangtze River together and fled to the south to escape the war.
But in the end, Wang Langya successfully established a new dynasty-the Eastern Jin Dynasty, with its capital in today's Nanjing, and then derived a new saying, that is, "Five horses crossing the river, one Ma Chenglong."
Generally speaking, five horses crossed the Yangtze River, and finally one of them became a dragon. This auspicious symbol means that five princes crossed the river at the same time, and the prince who finally established a new dynasty was the descendant of the dragon.
Si Marui, the legendary dragon king, was the founding emperor of the Eastern Jin Dynasty, because the five princes crossed the river to avoid the war, and it was most important to save their lives. They never expected such an achievement, which made the story of crossing the river with five horses more historic.
Si Marui is the dragon in the allusions of crossing the river with five horses. So the story of five horses crossing the river became more legendary.
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Five horses:
Langya Wang Si Marui 1
Si Marui (276-323) was born in Wenxian County, Hanoi (now Wenxian County, Henan Province), that is, Emperor Jin and the founding emperor of the Eastern Jin Dynasty (reigned 365438-08-323). Great-grandson of Sima Yi, Xuan Di, grandson of Sima _, evil king, son of Sima, son of Emperor Wu of Jin Dynasty.
2. Xiyang Wang Sima
Sima _ (284-329) was born in Hanoi County (now wen county, Henan Province). Imperial clan and minister of the Jin Dynasty, grandson of Xuan Di Sima Yi, emperor of the Jin Dynasty, and third son of Sima Liang, king of Runan Wencheng.
3. King Sima Zong of Nanton
Sima zong (? -326), the word Yanchou, was born in Wenxian County, Hanoi County (now Wenxian County, Henan Province). Imperial clan minister of Jin Dynasty, grandson of Sima Yi, emperor Xuan Di of Jin Dynasty, and fourth son of Sima Liang, King of Runan Wencheng.
4. Sima You, King of Runan
Member of the imperial clan in the Western Jin Dynasty, son of Sima Cheng, king of Wuyi County, and heir of Sima Yi. There is no other record of Sima You, the king of Wuyi County, in the Book of Jin.
5. Wang Pengcheng Sima
Sima _ (? -342), the word, was born in Wenxian County, Hanoi (now Wenxian County, Henan Province), the great-grandson of Sima Yi, the younger brother of Emperor Sima Yi, the great-grandson of Sima Quan, the great-grandson of Peng Cheng, the son of Sima Shi in Kang Wang, Peng Cheng, the imperial clan and vassal of Jin Dynasty.
Baidu Encyclopedia-Five Horses Crossing the River