The Turkic peoples are a collection of diverse ethnic groups of West, Central, East, and North Asia as well as parts of Europe, who speak Turkic languages. According to historians and linguists, the Proto-Turkic language originated in Central-East Asia region, potentially in Mongolia or Tuva. Initially, Proto-Turkic speakers were potentially both hunter-gatherers and farmers, but later became nomadic pastoralists. Early and medieval Turkic groups exhibited a wide range of both East Asian and West-Eurasian physical appearances and genetic origins, in part through long-term contact with neighboring peoples such as Iranian, Mongolic, Tocharians, Yeniseian people, and others. Many vastly differing ethnic groups have throughout history become part of the Turkic peoples through language shift, acculturation, conquest, intermixing, adoption, and religious conversion. Nevertheless, Turkic peoples share, to varying degrees, non-linguistic characteristics like cultural traits, ancestry from a common gene pool, and historical experiences. Some of the most notable modern Turkic ethnic groups include the Altai people, Azerbaijanis, Chuvash people, Gagauz people, Kazakhs, Kyrgyz people, Turkmens, Turkish people, Tuvans, Uyghurs, Uzbeks, and Yakuts. Etymology The first known mention of the term Turk (Old Turkic: 𐱅𐰇𐰼𐰰 Türük or 𐱅𐰇𐰼𐰰:𐰜𐰇𐰛 Kök Türük, , Pinyin: Tūjué < Middle Chinese *tɦut-kyat < *dwət-kuɑt, Old Tibetan: drugu) applied to only one Turkic group, namely, the Göktürks, who were also mentioned, as türüg ~ török, in the 6th-century Khüis Tolgoi inscription, most likely not later than 587 AD. A letter by Ishbara Qaghan to Emperor Wen of Sui in 585 described him as "the Great Turk Khan". The Bugut (584 CE) and Orkhon inscriptions (735 CE) use the terms Türküt, Türk and Türük. During the first century CE, Pomponius Mela refers to the Turcae in the forests north of the Sea of Azov, and Pliny the Elder lists the Tyrcae among the people of the same area. However, English archaeologist Ellis Minns contended that Tyrcae Τῦρκαι is "a false correction" for Iyrcae Ἱύρκαι, a people who dwelt beyond the Thyssagetae, according to Herodotus (Histories, iv. 22), and were likely Ugric ancestors of Magyars. There are references to certain groups in antiquity whose names might have been foreign transcriptions of Tür(ü)k, such as Togarma, Turukha/Turuška, Turukku and so on; but the information gap is so substantial that any connection of these ancient people to the modern Turks is not possible. It is generally accepted that the name Türk is ultimately derived from the Old-Turkic migration-term 𐱅𐰇𐰼𐰰 Türük/Törük,< which means 'created,