English: Tapan Union of Turkic Varsaks is a historical, tribal, geographical, territorial union of nine semi-nomadic obas (tribal villages), formerly known as Karsak (also Garsak, Karsag, Harsag, Uarsag), they are known to be one of the earliest Turkic tribes who became the natives of Anatolia. Karsak tribe was recorded around modern-day Kars (northeasternmost Turkey), and they were mentioned among the tribes of Velentür Union. Velentür, Vanandur etc. namings were some of Armenian reflections for the name of Turkic Onogur tribal union around BC 200s and BC 100s, until AD 100s. There is an ancient town called Onoguris in modern-day Georgia, recorded in Byzantine sources, after defeating Bulgars of Caucasus (Onogurs), Byzantines renamed the town as "Stephanopolis". Additionally, Kars city was known as both Kars and Vanand in Armenian, Byzantine, Arabic, Persian and Turkish sources. Vanand was one of the reflections of the name Onogur. Onogurs in Latin and Byzantine sources also mentioned as Onogundur, Ongundur, Ulundur, Vanandor, Nandor, Ongar, Ungar etc. Name Karsak on the other hand, is the name of steppe fox in Turkic. That same steppe fox is known as "corsac" in English also, reflecting the tribal name of Karsak. Karsak tribe's tamga and ongon (sign, totem) was the corsac fox.

Onogurs were not only present in the Caucasus, the remaining urheimat population of Onogurs continued to live around/between north of the Caucasus and the Urals, but many centuries later (around 400s and 500s, Oghur tribes, collectively) they firstly arrived in the region around/between modern-day Kyiv, Crimea and Bessarabia (called Etelköz in Hungarian sources), then some centuries later, they moved westward into the lands of Turkic Avars of Avaria to seek asylum after losing a bloody internal war against Turkic Khazars of Khazaria, around modern-day Hungary and made Hungary their last/ultimate homeland (around AD 800s). This occurred centuries after first Onogurs left Etelköz (north and northwest of Crimea) and founded First Bulgar Khaganate (First Bulgarian Kingdom) of the Danube (around AD 600s).

Hungary's ancient, medieval, old, historical former name was Onogury or Onoguria and Onogurians or Onogurs were recorded as "Tourkoi (Turks)" and "Tourkia (Turkey)" in Byzantine sources. In linguistics, Ugric-Turkic War is ended but according to some, Hungarian (Magyar, also Majar in Turkic Ottoman and Kazakh languages) language is standing alone as the last earliest form of Proto-Oguric aka Proto-Bulgar or Proto-Hunno-Bulgar Turkic language. This language is sometimes interpreted as it was the collective language of Proto-Turks, hence Proto-Turkic language was equal to Proto-Bulgar/Oghur. It is suggested that so-called last surviving Oghur language, namely Chuvash language protected their language in a different way because the Hungary Bulgars and Chuvashia Bulgars (they were known as Sabir and then Suvar) separated their ways a very long time ago; Onogurian, Utrigur, Kutrigur Bulgars left their urheimat around the Urals firstly between BC 200s and AD 100s towards the south of the Caucasus, then AD 400s-500s towards Etelköz (northwest/north of Crimea), then AD 600s towards modern-day Bulgaria (by the king's will and bloodily, they changed their language around AD 800s), then lastly around AD 800s towards modern-day Hungary.