In the battles of Magnano and Cassano, the Austrians and allied Russian Empire forces swept the French from much of northern Italy in April 1799. MacDonald collected the French occupying forces in south and central Italy into an army and marched north to retrieve the situation. Bursting out of the Apennine Mountains, the French divisions of Jean-Baptiste Olivier and François Watrin mauled Hohenzollern's division at Modena. MacDonald swung west to fight the Coalition forces. The next action would be the Battle of the Trebbia (1799) from 17 to 19 June.