In late 1848, Schlik led a legion of 8,000 men through the Dukla Pass into the Kingdom of Hungary before Alfred I, Prince of Windisch-Grätz started to attack Hungary in the Winter Campaign of the Hungarian Revolution of 1848. On 11 December Schlik defeated Sándor Pulszky in the Battle of Budamér and occupied Eperjes (now Prešov, Slovakia) and Kassa (now Košice, Slovakia).