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The 209th Infantry Division was one of the divisions deployed in the immediate leadup to the Invasion of Poland as part of the third Aufstellungswelle. It was first formed on 26 August 1939 in Komotau in Wehrkreis IV. It initially consisted of the Infantry Regiments 304, 394, and 414, as well as Artillery Regiment 209.
Following an order from 24 July 1940, the division was dissolved on 24 August 1940. The Infantry Regiments 304 and 394 became the Rifle Regiments 304 and 394 with the 2nd Panzer Division and the 3rd Panzer Division. The division's engineers joined the 11th Panzer Division, the intelligence detachment became part of the newly formed 18th Panzer Division. The Infantry Regiment 414 was used to guard PoWs.
^ Tessin, Georg (1977). "209. Infanterie-Division". Die Landstreitkräfte 201-280. Verbände und Truppen der deutschen Wehrmacht und Waffen-SS im Zweiten Weltkrieg 1939-1945 (in German). Vol. 8. Osnabrück: Biblio Verlag. pp. 39–42. ISBN3764810971.