During the Seven Years' War, victory of Frederick the Great over an Austrian army led by Charles of Lorraine 6 May 1757 outside Prague.
Prague, then in Bohemia, was held by Charles with 75,000 Austrian troops, and Frederick began his campaign of 1757 by marching on the city with a 64,000-strong Prussian army. Frederick opened with a strong attack against the Austrian left flank, followed by a general advance. The battle was hotly contested and things were not going well for Frederick until he threw a cavalry attack against each of the Austrian wings. This broke their defense and drove them into a hasty retreat into the fortified city of Prague, losing over 10,000 casualties and 4,300 prisoners. Prussian losses were over 13,000 but they held the field and moved on to lay siege to the city.