The Saar Offensive was a French ground operation into Saarland, Germany, during the early stages of World War II, from 7 to 16 September 1939. The purpose of the attack was to assist Poland, which was then under invasion. The all-out assault was to have been carried out by roughly 40 divisions, including one armored division, three mechanised divisions, 78 artillery regiments and 40 tank battalions.