The battle of France marked the end of the so called Phony War. The uncertain period of the Second World War which saw neither side commit to serious military action, and witnessed the German forces invade France and surrounding countries. Despite similar numbers in their respective forces the Germans managed to overcome the French, boosted by the British expeditionary force and Belgian and Dutch divisions. This was mainly due to the superior German training and communication, and the Allies' wrong held belief that the Maginot line- the heavily fortified French border with Germany- would a) hold and b) that the Germans would concentrate their efforts on it. In the event the German attacked through Belgium and Holland, thereby rendering the line an expensive mistake. The Germans devastated the inexperienced French and there allied troops and took the entire country soon after.