Why do some people say that their ancestors were Sophora japonica in Hongtong County, Shanxi Province?

There is a folk song circulating in the vast area of Hebei Province: "Ask me where my ancestors came from? Shanxi Hongdong big locust tree. " "Ask me what's the name of my hometown? The old man's nest under the big banyan tree. " That is to say, his ancestors migrated from the big locust tree in Hongdong, Shanxi. If you want to ask: Why did you move? Then we should start with "the prince sweeps the king". The Prince of Yan was the fourth son of Zhu Yuanzhang, the great ancestor of Ming Dynasty, named Di, who led a heavy army to suppress Shoudu (present-day Beijing). Zhu Biao, the eldest son of Zhu Yuanzhang, died young. After Zhu Yuanzhang's death, according to the tradition of "dragon" instead of "emperor", Zhu Yun, the eldest son of Zhu Biao, became emperor, and the title was established. At the suggestion of Qi Tai, Huang Zicheng and other ministers, Wen Jian greatly reduced the vassals and deprived the enfeoffed uncles all over the country of their military power. The prince borrowed the name of Huang Zhi and rose up, so-called "Jingnan". Emperor Wen Jian sent troops to suppress the rebellion. So in Hebei and Shandong, we fought for three or four years. History books call it "the battle of Jingnan", and folklore calls it "the prince sweeping the north" During this period, the people were destroyed by war and attacked by natural disasters. "Nine times out of ten, the village was destroyed, leaving only 1 1.2 people." "When Chun Yan came back, there was no place to live, and the bare land was thousands of miles away." According to historical records, this place in Hebei was "white bones and green", "devastated" and desolate everywhere. However, there was no war in Hongdong, Shanxi. The weather is good every year, the surrounding area is peaceful, and the people live and work in peace and contentment. The battle of Jingnan ended with Judy's victory. 1403, Yan captured Nanjing, and Emperor Jianwen disappeared in the war. The prince of Yan is the emperor, and Yongle's name is for the Ming Dynasty. Cheng Zu of Ming Dynasty was an outstanding emperor in history. He vigorously developed production and tried his best to restore Hebei's economy. In the early years of Yongle, the imperial edict from Shaanxi was "divided into Dingding and Nanguan areas in Ding Yu Town, which were occupied by the people", so the central government at that time set up an immigration agency in Hongtong County to handle immigration matters. According to legend, there is an ancient pagoda tree here. So among Hebei people, "Where are our ancestors?" ? The saying of the old locust tree in Hongdong, Shanxi.