In the spring of 1799 the Habsburg and Russian armies ousted the French from much of northern Italy after the battles of Magnano and Cassano and they placed the key fortress of Mantua under siege. Assembling the French occupation forces of southern and central Italy into an army, MacDonald moved north to challenge his enemies. Rather than playing safe by moving along the west coast road, MacDonald boldly chose to move east of the Apennine Mountains, hoping to be supported by Jean Victor Marie Moreau's French army. After brushing aside a much smaller Austrian force at Modena, MacDonald's army swept west along the south bank of the Po River. Suvorov swiftly concentrated his Russians and the allied Austrians of Michael von Melas to block the French move.