In the Rhine campaign of 1795 (April 1795 to January 1796) during the War of the First Coalition, two Habsburg Austrian armies under the command of François Sébastien Charles Joseph de Croix, Count of Clerfayt, defeated two Republican French armies attempting to invade the south German states of the Holy Roman Empire. At the start of the campaign, the French Army of the Sambre and Meuse, led by Jean-Baptiste Jourdan, confronted Clerfayt's Army of the Lower Rhine in the north, while the French Army of the Rhine and Moselle, under Jean-Charles Pichegru, lay opposite Dagobert Sigmund von Wurmser's Army of the Upper Rhine in the south. A French offensive failed in early summer but in August, Jourdan crossed the Rhine and quickly seized Düsseldorf. The Army of the Sambre and Meuse advanced south to the Main River, isolating Mainz. Pichegru's army made a surprise capture of Mannheim and both French armies held significant footholds on the east bank of the Rhine.
The promising start to the French offensive ended when Pichegru lost an opportunity to seize Clerfayt's supply base in the Battle of Handschuhsheim. While Pichegru delayed, Clerfayt massed against Jourdan, beat him at the Battle of Höchst in October and forced most of the Army of the Sambre and Meuse to retreat to the west bank of the Rhine. At about the same time, Wurmser sealed off the French bridgehead at Mannheim. With Jourdan temporarily out of the picture, the Austrians defeated the left wing of the Army of the Rhine and Moselle at the Battle of Mainz and moved down the west bank. In November, Clerfayt defeated Pichegru at the Battle of Pfeddersheim and ended the Siege of Mannheim. In January 1796, Clerfayt concluded an armistice with the French, allowing the Austrians to retain large portions of the west bank. During the campaign, Pichegru entered into negotiations with French Royalists. It is debatable whether Pichegru's treason, his bad generalship or the unrealistic expectations of the war planners in Paris was the actual cause of the French failure.
Background
The rulers of Europe initially viewed the French Revolution as an internal dispute between the French king Louis XVI and his subjects. As revolutionary rhetoric grew more strident, the monarchs of Europe declared their interests as one with those of Louis and his family. The Declaration of Pillnitz (27 August 1791) threatened ambiguous, serious consequences if anything should happen to the French royal family. With Habsburg, Prussian and British support, French émigrés continued to agitate for a counter-revolution. On 20 April 1792, the French National Convention declared war on the Habsburg monarchy, pushing Great Britain, the Kingdom of Portugal, the Ottoman Empire and the Holy Roman Empire into the War of the First Coalition (1792–1798).
After initial successes in 1792, French fortunes varied in 1793 and 1794. By 1794, the armies of the French Republic were in a state of disruption. Some of the old regime units, especially the cavalry, had defected en masse with Louis' brothers and cousins. Radicalization of the Revolution after 1793 encouraged the suspicion of treason in every loss. The most radical of the revolutionaries purged the military of all men conceivably loyal to the Ancien Régime (Old Regime), resulting in the loss of experienced leadership and non-commissioned officers. To fill the ranks of the army, a levée en masse (mass conscription) created a new kind of army with thousands of illiterate, untrained men under the command of officers whose principal qualifications may have been their loyalty to the Revolution instead their military acumen. The formation of new demi-brigades merged the old military units with new revolutionary formations: each demi-brigade included one unit of the old royal army and two created from the mass conscription. The French Directory believed that war should pay for itself and did not budget to pay, feed or equip its troops, leaving them to scavenge for their needs from the villages and towns where they were stationed. By early 1795, this newly structured and expanded army had made itself odious throughout France through its rapacious dependence upon the countryside for material support, its general lawlessness, and its undisciplined behavior.