The old name (until 1775) is Yaik. The ancient name is mentioned by Ptolemy as Daix. Hydronym of Turkic origin (jajyk - "spread, wide"). The old name of the river has been preserved in the Kazakh, Nogai and Bashkir languages. In some texts, the river is mentioned under the name Rhymn, Rymn (lat. Rhymnus fluvius), which is also attributed to the Volga, Emba, Big and Small Uzen; on the maps of medieval European cartographers, the modern Ural River was often indicated as Rhymnus or Rhymnicus. The first mention in the surviving Russian chronicles dates back to 1140: “Mstislav drove the Polovtsy beyond the Don, beyond the Volga, beyond Yaik.”
In Russia, the name Yaik was changed to Ural in 1775 by decree of Catherine II, after the suppression of the Peasants' War led by Pugachev, in which the Bashkirs and Yaik Cossacks actively participated.
