The Battle of Montcornet took place during which major conflict of the 20th century?

The Battle of Montcornet, on 17 May 1940 took place during the Battle of France in World War II. On 10 May 1940, the Third Reich had launched a vast offensive against the Netherlands, Belgium and France. After the German breakthrough in the Battle of Sedan on 13 May, the Germans had driven the French troops to a hasty retreat.

The French 4e Division cuirassée (Colonel Charles de Gaulle), attacked the German-held village of Montcornet with over 200 tanks. The French drove off the Germans but later had to retreat due to lack of support and the intervention of the Luftwaffe.

De Gaulle had just taken command of the new 4e Division cuirassée (4e DCr) on 12 May as the Germans were fighting to break through. That day, with three tank battalions assembled, less than a third of his paper strength, he was summoned to headquarters and told to attack to gain time for the Sixth Army (General Robert Touchon) to redeploy from the Maginot Line to the Aisne; it was his chance to implement his ideas of tank warfare.

The French lost 23 tanks in the attack, while taking around 130 German prisoners. De Gaulle fought another engagement at the Battle of Abbeville.