Ernest (German: Ernst), known as Ernest the Brave (Ernst der Tapfere), was the Margrave of Austria from 1055 to his death in 1075. He was a member of the House of Babenberg.
He was born to Margrave Adalbert of Austria and his wife Frozza Orseolo, daughter of Doge Otto Orseolo of Venice. He increased the territory of his margraviate by amalgamating the Bohemian and Hungarian frontier marches up to the Thaya, March and Leitha rivers in what is today Lower Austria. In his time, the colonisation of the remote Waldviertel region was begun by his ministeriales, the Kuenring knights.
Ernest received his epithet due to his fighting against King Béla I of Hungary and his son Géza I on behalf of their rival Solomon according to the chronicler Lambert of Hersfeld. In the commencing Investiture Controversy, he sided with King Henry IV of Germany and battled against the Saxons, dying at the Battle of Langensalza.