[1] From 1931 to early 1933, Feßmann led the motorised battalion of the 2nd Artillery Regiment, before a period in the Soviet Union at the Reichswehr's secret Panzertruppenschule (armoured training school) at Kazan.

[5] Most of its panzer companies, which initially each consisted of only eight tanks, began equipping and training with Panzerkampfwagen I (armored fighting vehicle mark I).

[1] Appointed commander of the newly formed 267th Infantry Division on 26 August 1939, Feßmann served on the Western Front and took part in the invasions of Belgium and France.

After the fall of France in May 1940, his division garrisoned a sector along the English Channel for a year, before being transferred east for Operation Barbarossa.

Before the invasion of the Soviet Union began, he was replaced as divisional commander by Generalmajor Friedrich-Karl von Wachter (generalmajor is equivalent in rank to a brigadier general in the United States Army).