Wikipedia
· Touman Teoman( Mongolian: Tümen, whom we know about from Han-Dynasty histories, which based themselves on documents contemporary with him and write the name as Chinese 頭曼, this spelling Touman coming from the characters' Modern-Standard Mandarin pronunciation), or T'u-man, – was the earliest known Xiongnu chanyu (匈奴單于), reigning from c. 220 to 209 BCE. The name Touman is likely related to a word meaning '10,000, a myriad', which was widely borrowed between language-families in, most plausibly, the order indicated by the following representative list of its forms: Modern Persian (which includes the Tajik and Dari dialects of it) tōmān ~ tūmān, Mongolian tümen, Old Turkic tümän, East Tocharian tmāṃ, West Tocharian t māne, which possibly even includes Old Chinese and later 萬, whose pronunciation is reconstructable as for instance an early Middle Chinese *muanʰ. Note however that our only certain evidence this number-word already existed around and before Touman's life-time would be the Chinese (if it indeed does belong on the list, rather than being an unrelated, similar-looking word); not until many centuries after he lived are the other languages with this word in them first attested.
By the time the Qin Dynasty conquered the other six states and began its reign over a unified China in 221 BCE, the nomadic Xiongnu had grown into a powerful invading force in the north and started expanding both east and west.
At the time the Donghu (東胡) or 'Eastern Barbarians' were very powerful and the Yuezhi flourishing. Emperor Qin Shi Huang, the first emperor of the Qin Dynasty, sent a 100,000-strong army headed by General Meng Tian to drive the Xiongnu northward for 1,000 li (about 416 km).
"Touman, unable to hold out against the Qin forces, had withdrawn to the far north, where he held out for over ten years."Some time after the death of Meng Tian in 210 BCE, the Xiongnu "once again began to infiltrate south of the bend of the Yellow River until they had established themselves along the old border of China."
Touman, wishing to favour a son of another consort, sent his eldest son, Modu (冒頓), as a hostage to the Yuezhi, and then made a sudden attack on them. The Yuezhi were about to kill Modu when he managed to steal a fast horse and escape back to the Xiongnu.
Touman, impressed with his bravery, put him in command of a force of 10,000 horsemen. However, Modu trained his men well and, in 209 BCE, killed his father and, after killing his stepmother, younger brother, and the high officials who refused to take orders from him, established himself as Chanyu.
With his new combined military force, Modu was able to establish the Xiongnu empire.
A Han-Dynasty history, the Han shu (in its juan 94's "upper" section) recounts the end of Touman’s life in vivid language, as follows (literal English translation, to preserve flavor of original, then the Classical Chinese for the benefit of those who can appreciate that too).
... The chanyu[, Touman,] had a son and heir, by name called Modu. Later, he had a beloved khanum, who gave birth to a young[er] son. Touman wanted, casting aside Modu, to install the young son [in the position]. He managed to send Modu as a hostage to the Yuezhi. Upon Modu having become a hostage, Touman quickly attacked the Yuezhi. The Yuezhi wanted to kill Modu. Modu stole their good horse(s), rode, went away, and returned home. Touman took it as strength and ordered that he have command of 10,000 riders. Modu managed to make whistling arrowheads and [with them] practiced constraining his riders to shoot. He gave an order, saying: "Those who do not always shoot at something shot at by [an arrow with] a whistling arrowhead will be beheaded." He conducted hunting for [game-]animals. He had some not shooting at something the whistling arrowhead(s) [had] shot at, and he on the spot beheaded them. [That] being done, Modu with a whistling arrowhead shot at a good horse of his own. At [his] left and right, some did not at all dare to shoot. Modu straightaway beheaded them. [Next,] he waited, a while passed, [then,] again with a whistling arrowhead, he shot at his own beloved wife. At [his] left and right, he had some who were quite afraid and did not dare shoot, and he again beheaded them. A while passed. Modu went out hunting. With a whistling arrowhead, he shot at a good horse of [Touman,] the chanyu's. At [his] left and right, all shot at it. Modu thereupon knew that his left and right could be used [for the task]. He went along on a hunt of his father, the chanyu, Touman's, and with a whistling arrowhead shot at Touman. His left and right, all following the whistling arrowhead, shot at and killed Touman. They put to death both his stepmother and the younger brother and even some important retainers who did not obey and go along. Modu thereupon installed himself and became chanyu.