The Battle of Wels (10/12 August 943) was fought between a joint Bavarian–Carantanian army and a Hungarian force near Wels in the Traungau, on the plain of the Welser Heide, nowadays a part of Austria. The battle took place at the height of the Hungarian invasions of Europe. The Bavarians and Carantanians were victorious under the command of the Bavarian leader Berthold. The victory is mentioned widely in contemporary histories. It is mentioned in Widukind of Corvey's Deeds of the Saxons, in Hermann of Reichenau's Chronicon and by Adalbert of Weissenburg in his continuation of the Chronicon of Regino of Prüm. It is also mentioned in the Annals of Saint Gall, the Annals of Salzburg and the , and in the necrology of Freising Cathedral.