Orhon inscriptions, oldest extant Turkish writings, discovered in the valley of the Orhon River, northern Mongolia, in 1889 and deciphered in 1893 by the Danish philologist Vilhelm Thomsen. They are on two large monuments, erected in ad 732 and 735 in honour of the Turkish prince Kül (d. 731) and his brother the emperor Bilge (d. 734), and are carved in a script used also for inscriptions found in Mongolia, Siberia, and Eastern Turkistan and called by Thomsen “Turkish runes.” They relate in epic language the legendary origins of the Turks, the golden age of their history, their subjugation by the Chinese, and their liberation by Bilge. The polished style of the writings suggests considerable earlier development of the Turkish language.