Xinmin dialect originated from Shang and Zhou Mandarin, and was separated from Central Plains Chinese in the late Tang and early Song Dynasties. Up to now, a large number of pre-Qin rhymes are still preserved, which can be seen from Hakka reading pre-Qin classics and Xinmin dialect's Tang and Song poems. Mandarin can't rhyme, but Hakka can rhyme. Some scholars even pointed out that Xinmin dialect originated from the standard "Mandarin" in the Tang and Song Dynasties.
Based on the comprehensive research of relevant data, due to the war caused by the invasion of the northern minorities (that is, Wuluanhua) into the Central Plains and the rapid expansion of the population in the Central Plains, Hakka ancestors began to move south from the Eastern Jin Dynasty. At present, the academic circles recognize the "five-time theory" of large-scale migration. The first time was the Yongjia Rebellion in the Eastern Jin Dynasty to the Sui and Tang Dynasties, when he moved from Henan to Jiangxi. The second time, at the end of the Tang Dynasty and the beginning of the Song Dynasty, Huang Chao forced the Han people from Henan, Anhui and Jiangxi to move south to western Fujian and southern Jiangxi, and entered the Song Dynasty to form a Hakka clan. The third time was when the Song Dynasty was dying, and the Han people who went south arrived in eastern Guangdong and northern Guangdong. The fourth time, during the period from Kangxi to Ganjia in Qing Dynasty, the Qing court implemented the population policy of "Huguang filling Sichuan". Due to the influence of Zheng Chenggong's anti-Qing and anti-Ming, some Hakkas went to Sichuan, Taiwan, Hunan and Guangxi. The fifth time, after Ganjia, due to the subversive activities of the Manchu dynasty to suppress the Han people in the south, the Hakkas distributed in the northeast and central Guangdong migrated to western Guangdong and Hainan. In modern times, some Hakkas migrated overseas, mainly in Europe, America and Southeast Asia. [4]