The battle of Mouscron was the first significant French victory during their attack into western Belgium at the start of 1794, the campaign that would eventually expel the Allies from the former Austrian Netherlands. The French plan for the 1794 campaigning season involved offensives at both ends of the Allied line in Belgium, with the main attack coming at the western end of the Allied line, in maritime Flanders. This area was defended by an Austrian army commanded by General Clerfayt, who had his headquarters at Tournai.
The main Allied plan for 1794 was rather less ambitious, and began with an attack on Landrecies, roughly in the centre of the Allied lines. This siege began on 17 April, and would end in one of the year's rare Allied assaults, but its result would have little significance.
The first move in the main French offensive came on 23 April, when a French force moved from Cambrai to threaten the Allied covering force under General Wurmb at Denain. This forced Clerfayt to move south from his base at Tournai, away from the real danger area.
Three French armies were involved in the main offensive. General Michaud, with 12,000 men, advanced from Dunkirk into the gap between Nieuport and Ypres, sweeping away a number of Allied posts. To his right General Moreau with 21,000 men advanced from Cassel towards Ypres. Finally, at the right of the French line General Souham, with 30,000 men and accompanied by General Pichegru, the commander of the Armée du Nord, advanced north-east from Lille and captured Courtrai. After leaving some of his men at Ypres, Moreau advanced east to besiege Menin.
The Austrian position was temporarily saved by General Oynhausen, who managed to hold onto his position at Dottignies (just to the east of Souham's line of advance from Lille to Courtrai), and then recovered Mouscron.
On 26 April, during the battle of Landrecies, the French General Chappuis was captured, along with a complete set of Pichegru's orders for the offensive in the west. The Allied commander, the Prince of Saxe-Coburg, immediately sent reinforces towards the fighting, and ordered Clerfayt to return north from Denain. On the night of 28 April Clerfaye reached Mouscron, bringing the number of troops present there up to 10,000.
Despite still being heavily outnumbered Clerfaye planned to make an attempt to lift the siege of Menin on 30 April, but the French attacked first. On 29 April one column under General Souham attacked Clerfaye from the front, while another under General Bertin hit him from the left and rear.
The Austrians were outnumbered by three to one, but managed to hold their ground for some time. Clerfaye was eventually forced to order a retreat, which soon turned into a rout. Fortunately five battalions of the reinforcements sent from Landrecies reached Dottignies in time to rally Clerfaye's men, but only after they had suffered 2,000 casualties. The reinforced Austrian force retreated east to Espierres, on the Scheldt, while on the day after the battle the garrison of Menin fought its way to safety.