The opponents were a Bavarian army led by duke Henry XI and the Hungarian army under the leadership of king Géza II and his uncle, the palatineBeloš Vukanović, who formerly served as regent and tutor for the underage king. Both sides lined up significant armies. Before the battle, Géza was girded with a sword, meaning that the young king entered adulthood in the eyes of his people.
Henry's scouts didn't manage to inform him properly about the movement of the Hungarian army. Due to this, he didn't know that the Hungarians crossed the Leitha and, seeing a lot of smoke, he thought that they retreated and set their encampments on fire. When he launched his assault, he was surprised when he met the Hungarian assault half way through. Despite this, the Germans heavy cavalry gained the upper hand against the Székely and Pecheneg vanguard, who suffered hefty losses.
Then intense fighting began between the Bavarian forces and the Hungarian second line of defense. In the end, Belos managed to get behind the Germans, turning the tides of the battle. Géza's cavalry charge of about 12 000 reservists gave the final blow to them. Henry was forced to retreat and the Hungarians pursued them until the Fischa river.
References
Kristó, Gyula: Háborúk és hadviselés az Árpádok korában. Szukits Könyvkiadó, Szeged, 2003. ISBN9639441872
Makk, Ferenc: Magyarország a 12. században. Gondolat, Budapest, 1986. ISBN9632816609
Magyarország hadtörténete két kötetben (ed.: Liptai, Ervin). Zrínyi Katonai Kiadó, Budapest, 1985. ISBN9633263379
kk, Ferenc: Az Árpádok – fejedelmek és királyok. Szukits Könyvkiadó, Szeged, 2003. ISBN9639278483)