Entering the Austrian Army in 1801, Haynau saw action throughout the Napoleonic Wars and remained in service after the Congress of Vienna (1814–15). During the revolutions of 1848–49, he campaigned in Italy, where he marred his undoubted military abilities by the inordinately severe repression of a rising in Brescia. Moving to Hungary in command of an army corps in 1849, Haynau again, though successful in the field, used what many thought was undue harshness. He retired in 1850 and toured Europe, but his reputation was such that he was exposed to mob violence during his visits to London in 1850 and Brussels in 1852.