From the Wikipedia article Asena:
The Old Turkic name was Türük, Kök Türük, or Türük.
According to Turkic mythology, they were known in Chinese historical sources as Tujue (Tu-chueh; Chinese: 突厥; pinyin: Tūjué;Wade–Giles: T’u-chüeh; Middle Chinese: dʰuət-kĭwɐt). According to Chinese sources, the meaning of the word Tujue was “combat helmet” (Chinese: 兜鍪; pinyin: Dōumóu; Wade–Giles: Tou-mou), reportedly because the shape of the Altai Mountains, where they lived, was similar to a combat helmet.
The name Göktürk is said to mean “Celestial Turks”. This is consistent with “the cult of heavenly ordained rule” which was a recurrent element of Altaic political culture and as such may have been imbibed by the Göktürks from their predecessors in Mongolia. Similarly, the name of the ruling Ashina clan may derive from the Khotanese Sakā term for “deep blue”, āššɪna. The name might also derive from a Tungusic tribe related to Aisin.
The word Türk meant “strong” in Old Turkic. Gök means Sky in modern Turkish.
The Göktürk rulers originated from the Ashina clan, who first come to our attention in 439. The Book of Sui reports that in that year on October 18, the Tuoba ruler Emperor Taiwu of Northern Wei overthrew Juqu Mujian of the Northern Liang in eastern Gansu, whence 500 Ashina families fled northwest to the Rouran Khaganate in the vicinity of Gaochang.
According to the Book of Zhou and the History of the Northern Dynasties, the Ashina clan was a component of the Xiongnu confederation, but this connection is disputed, and according to the Book of Sui and the Tongdian, they were “mixed barbarians” (雜胡 / 杂胡, Pinyin: zá hú, Wade–Giles: tsa hu) from Pingliang. As part of the heterogeneous Rouran Khaganate, the Türks lived for generations north of the Altai Mountains, where they ‘engaged in metal working for the Rouran’. According to Denis Sinor, the rise to power of the Ashina clan represented an ‘internal revolution’ in the Rouran confederacy, rather than an external conquest. According to Charles Holcombe, the early Tujue population was rather heterogeneous and many of the names of Türk rulers are not even Turkic.
Legend tells of a young boy who survived a battle; a female wolf finds the injured child and nurses him back to health. The wolf, impregnated by the boy, escapes her enemies by crossing the Western Sea to a cave near the Qocho mountains and a city of the Tocharians, giving birth to ten half-wolf, half-human boys. Of these, Ashina becomes their leader and instaures the Ashina clan, which ruled over the Göktürk and other Turkic nomadic empires.
A branch of the Ashina, appear to have arrived in Japan in the Kofun Period around the 6th c. because they are mentioned in the semi-mythical genealogical accounts of the royal chronicles as the elderly ancestor-patriarch Ashina-zuchi (whose wife was Tenazuchi, and daughter Kushinada) from Izumo. Ashina surviving lineages are noted to form the Ashina clan, descended from the daimyo of Miura, and the Taira…see Ashina-zuchi.
Epigraphs of ancient Turkic people discovered in Mongolia July 17, 2013 The Asahi Shimbun
By KUNIHIKO IMAI/ Senior Staff Writer
OSAKA–Two massive slabs of stone inscribed in ancient Turkic script have been found on the steppes of eastern Mongolia, the first such discovery in over a century, a Japanese researcher said July 16.
The epigraphs date from the mid-eighth century, said Takashi Osawa, a professor of ancient Turkic history at Osaka University’s graduate school.
He said the finds may offer invaluable clues to the political systems and institutions of the Gokturk people, who faced the Sui and Tang dynasties in China in times of peace and war as they reigned over the steppes of Central Asia.
Osawa said he and researchers from the Institute of Archaeology of the Mongolian Academy of Sciences discovered remnants of two giant epigraphs in May at an archaeological site called Dongoin shiree. It is near Mount Delgerkhaan, 400 kilometers southeast of Ulan Bator, the Mongolian capital.
The epigraphs measure 4 meters and 3 meters, respectively.
Combined, they are inscribed with 2,832 symbols, in 20 lines of ancient Turkic script.
Osawa, who deciphered the writing, said it describes the lamentation of people who have to leave their beloved families and homeland behind when they die.
“Oh, my home!” reads one inscription. Another reads: “Oh, my land!”
Signs engraved in the epigraphs indicate the artifacts likely represent epitaphs dedicated to members of the Ashina tribe, the reigning family of the Second Turkic Empire (682-744).
The Gokturks are the oldest nomadic people in Central Asia that left records of their own language in their own writing system.
The discovery is significant as it is the first of its kind since the three most renowned ancient Turkic inscriptions (Bilge Kaghan, Kol Tigin and Tonyukuk) were discovered in central Mongolia about 120 years ago, experts said.
“Other parts that remain buried in the ground may offer a record of the lives of the individuals commemorated,” Osawa said.
“Research on ancient Turkic script has centered on the re-reading of known inscriptions after a Danish linguist deciphered the writing in the late 19th century,” said Takao Moriyasu, a professor of Central Asian history at Kinki University. “The latest finds could help unravel new facts.”
The history of the Gokturk state started when Yili Kaghan founded the First Turkic Empire in 552.
Political maneuvering by the Sui Dynasty of China split the Gokturk nation into an eastern and a western part, with the East Turkic Empire succumbing to Tang China’s rule in 630. The Gokturks regained independence from Tang China to found the Second Turkic Empire in 682, only to be brought down by the Uighurs in 744.