Writers during the Western Zhou and Han dynasties derived ancestral lineages based on Shang dynasty-era legendary materials, while the Han dynasty historian Sima Qian's "Records of the Grand Historian" places the reign of the Yellow Emperor, the legendary leader of Youxiong tribes (), at the beginning of Chinese history. The Yellow Emperor is traditionally credited to have united with the neighbouring Shennong tribes after defeating their leader, the Yan Emperor, at the Battle of Banquan. The newly merged Yanhuang tribes then combined forces to defeat their common enemy from the east, Chiyou of the Jiuli () tribes, at the Battle of Zhuolu, and established their cultural dominance in the Central Plain region. To this day, modern Han Chinese refer themselves as "Descendants of Yan and Huang".