The Tabğaç (Chinese: 拓拔; Old Turkic: 𐱃𐰉𐰍𐰲) were initially a Xuŋa tribe, descending from the daughter of Ju-di-hou Darğa (且鞮侯), that defected to the Särbi following the collapse of the Xuŋa empire. Their descendants would establish the Wei dynasty (魏), commonly known as Northern Wei (北魏).
The earliest Tabğaç ancestor that had a posthumous name was Tabğaç Mao (毛) LH *mɑu, known as Emperor Cheng (成皇帝). Interestingly, the Taiping Yulan has Tun (屯) LH *duən instead of Mao. There is a chance that Tun was an abbreviation of Mao-tun (毛屯) LH *mɑu-duən, identical to the Xuŋa founder, Mao-dun (冒頓) LH *mək-tuən or Turkic Bağatur. The connection to Bağatur, however, goes beyond transcriptional reconstructions. For instance, the following Weishu narrative attributed to Tabğaç Mao is clearly describing the historical actions of Bağatur:
"Wise and martial, promoted by those near and far, he united the thirty-six states and the ninety-nine great tribes. His strength dominated the North and there was no one who did not submit to his rule."
Tabğaç Mao is thought to have lived somewhere in between 200 B.C.E. and 130 B.C.E. (Duthie, 2015). Thus, his legend must have been based on Bağatur, given that the Särbi tribes were under Xuŋa rule during those times. Accordingly, Tabğaç Mao was likely the historical Bağatur Darğa. The emperors listed as his successors; however, were likely made up, explaining why there were no Chinese emperors or darğas known by those names.
Nonetheless, the four emperors that ruled after Tabğaç Mao, or Bağatur Darğa, were as follows:
The Jie Emperor (節皇帝), Dai (貸) LH *tʰə,
The Zhuang Emperor (莊皇帝), Guan (觀) LH *kuɑn,
The Ming Emperor (明皇帝), Lou (樓) LH *l(i)o, and
The An Emperor (安皇帝), Yue (越) LH *wɑt.