France Launches Saar Offensive

French patrols cross the frontier into Germany near Saarbrucken, marking the beginning of the Saar offensive.

A total of 11 divisions advance along a 32 km frontage. There is negligible German opposition. The French mobilization is too slow and their tactical system too inflexible to permit any grander offensive operation. These gentle probes continue until September 17th when a larger advance is supposed to be made but is in fact cancelled because the Polish collapse makes it pointless.

The Saar Offensive was a French operation into Saarland on the German 1st Army defence sector in the early stages of World War II. The purpose of the attack was to assist Poland, which was then under attack. However, the assault was stopped and the French forces withdrew.

According to the Franco-Polish military convention, the French army was to start preparations for the major offensive three days after mobilisation started. The French forces were to effectively gain control over the area between the French border and the German lines and were to probe the German defences. On the fifteenth day of the mobilisation (that is on September 16), the French army was to start a full-scale assault on Germany. The pre-emptive mobilisation was started in France on August 26 and on September 1 full mobilisation was declared.

A French offensive in the Rhine valley began on September 7, four days after France declared war on Germany. Then, the Wehrmacht was occupied in the attack on Poland, and the French soldiers enjoyed a decisive numerical advantage along the border with Germany. However, the French did not take any action that was able to assist the Poles. Eleven French divisions advanced along a 32 km line near Saarbrücken against weak German opposition. The French army had advanced to a depth of eight kilometres and captured about 20 villages evacuated by the German army, without any resistance. However, the half-hearted offensive was halted after France seized the Warndt Forest, three square miles of heavily-mined German territory.

The attack did not result in any diversion of German troops. The all-out assault was to be carried out by roughly 40 divisions, including one armoured division, three mechanized divisions, 78 artillery regiments and 40 tank battalions. On September 12, the Anglo French Supreme War Council gathered for the first time at Abbeville in France. It was decided that all offensive actions were to be halted immediately. Maurice Gamelin ordered his troops to stop "not closer than 1 kilometre" from the German positions along the Siegfried Line. Poland was not notified of this decision. Instead, Gamelin informed marshal Edward Rydz-Śmigły that half of his divisions were in contact with the enemy, and that French advances had forced the Wehrmacht to withdraw at least six divisions from Poland. The following day the commander of the French Military Mission to Poland General Louis Faury informed the Polish chief of staff, general Wacław Stachiewicz, that the planned major offensive on the western front had to be postponed from September 17 to September 20. At the same time, French divisions were ordered to retreat to their barracks along the Maginot Line. The Phoney War had begun.