Saar Offensive

The Saar Offensive was a French ground invasion of Saarland, Germany, during the early stages of World War II, from 7 to 16 September 1939. The plans called for roughly 40 divisions, including one armored division, three mechanised divisions, 78 artillery regiments and 40 tank battalions to assist Poland, which was then under invasion, by attacking Germany's understrength western front. Although 30 divisions advanced to the border , the assault never happened. When the quick victory in Poland allowed Germany to reinforce its lines with homecoming troops, the offensive was stopped. The French forces eventually withdrew amid a German counter-offensive on 17 October.

According to the Franco-Polish military convention, the French Army was to start preparations for the major offensive three days after mobilization started. The French forces were to effectively gain control over the area between the French border and the Siegfried Line and were to probe the German defenses. The sector was defended by the German 1st Army. On the 15th day of the mobilization , the French Army was to start a full-scale assault on Germany. The pre-emptive mobilization was started in France on 26 August and on 1 September, full mobilization was declared.

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