Duke Frederick II of Austria, who arrived to assist Béla against the invaders, defeated a small Mongol troop near Pest. He seized prisoners, including Cumans from the Eurasian Steppes who had been forced to join the Mongols. When the citizens of Pest realized the presence of Cumans in the invading army, mass hysteria emerged.
Duke Frederick II of Austria came to aid Béla against invaders and defeated a small Mongol force near Pest. He captured prisoners, including Cumans from the Eurasian Steppes who had been forced into service with the Mongols. The sight of these Cumans in the invading army caused mass fear among the citizens of Pest.