The Battle on the Marchfeld (Morava Field) at Dürnkrut and Jedenspeigen took place on August 26, 1278 and was a decisive event for the history of Central Europe for the following centuries.

The opponents were King Ottokar II of Bohemia and an Imperial Army led by Rudolf I of Habsburg. The Imperial Army included Rudolph's troops as well as Hungarians and Cumans under Ladislaus IV of Hungary.

The Marchfeld (named after the Morava river) northeast of Vienna became the battlefield, as the armies consisting of knights could easily engage in battle on the flat terrain with hardly any forest. It is estimated that almost 80,000 men (about 40,000 on each side) were involved. Thus, it was likely the largest battle fought among knights during the middle ages. The estimated number of Hungarians and Cumans was 20,000.

In the late afternoon, Rudolf's forces finally could decide the battle in their favor. Ottokar did not die in battle, but was murdered during the retreat. It is suspected that he was the victim of a Carinthian knight's personal vendetta. The victory allowed the Habsburgs to take control over the Duchies of Austria, Styria, Carinthia and Carniola for the centuries to come (until 1918), while the Premyslid dynasty remained confined to the Bohemian lands.

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