[1][2] Godenau was born on 19 January 1903 in Netzort, Kreis Bromberg in Province of Posen within the German Empire, present-day Przyłęki.

[3] He joined the military service of Reichsmarine, the German Navy during the Weimar Republic, on 1 April 1925 with the 1st department of the standing ship division of the North Sea.

[5] During Operation Weserübung, the German the invasion of Denmark and Norway, Godenau commanded R-17.

On 9 April 1940, a German task force consisting of the torpedo boats Albatros and Kondor, accompanied by R-17 and R-21, heavily laden with troops attacked the Norwegian naval base at Horten which became the Battle of Horten Harbour.

[4] On 24 December, Godenau was promoted to Leutnant zur See (lieutenant at sea), effective as of 1 January 1942.