Bumin Qaghan (Old Turkic: , Bumïn qaγan, a.k.a. Bumın Kagan) or Illig Qaghan (Chinese: 伊利可汗, Pinyin: yīlì kěhàn, Wade–Giles: i-li k'o-han, died 552 AD) was the founder of the Turkic Khaganate. He was the eldest son of Ashina Tuwu (吐務 / 吐务). He was the chieftain of the Türks under the sovereignty of Rouran Khaganate. He is also mentioned as "Tumen" (土門, 吐門, commander of ten thousand) of the Rouran Khaganate.
According to History of Northern Dynasties and Zizhi Tongjian, in 545 Tumen's tribe started to rise and frequently invaded the western frontier of Wei. The chancellor of Western Wei Yuwen Tai sent An Nuopanto (Nanai-Banda, a Sogdian from Bukhara) to Kök Türks to greet its chieftain Tumen to try to establish commercial relationship. In 546, Tumen presented tribute to Western Wei.
And in the same year he put down a revolt of the Tiele tribes against their overlords the Rouran Khaganate. He took advantage of this success and requested a Rouran princess in marriage. But the qaghan of Rouran Anagui refused this request and sent to Bumin a mission and message: You are my blacksmith slave. How dare you utter these words?. Bumin got angry and killed Anagui's mission and cut all relationship with Rouran Khaganate.
Anagui's "blacksmith" (鍛奴 / 锻奴, Pinyin: duàn nú, Wade–Giles: tuan-nu) insult was recorded in Chinese chronicles and historians accepted that the Kök Türks were indeed blacksmith servants for the Rouran elite, and that "blacksmith slavery" may indicate a kind of vassalage system prevailed in Rouran society. Nevertheless, after this incident Bumin emerged as the leader of the revolt against Rouran.
In 551, Bumin requested a Western Wei princess in marriage. Yuwen Tai permitted it and sent Princess Changle of Western Wei to Bumin. In the same year when Emperor Wen of Western Wei died Bumin sent mission and gave two hundred horses.
The beginning of formal diplomatic relations with China propped up Bumin's authority among the Turks. He eventually united the local Turkic tribes and threw off the yoke of the Rouran domination.
In 552 Bumin's army defeated Anagui's forces at the north of Huaihuang and then Anagui committed suicide. With their defeat Bumin proclaimed himself "Illig Qaghan" and made his wife qaghatun. According to the Bilge Qaghan's memorial complex and the Kul Tigin's memorial complex, Bumin and Istemi ruled people by Turkic laws and they developed them.
Bumin died within several months after proclaiming himself Illig Qaghan. He was succeeded by his younger brother Istemi in the western part and by his son Issik Qaghan in the eastern part. In less than one century, his khaganate expanded to comprise most of Central Asia.