On 18 October 1943 he succeeded Harald Turner as the Chief of the Military Administration in Serbia, and he continued to fulfill both roles until late August 1944.

After complaints by senior Nazi officials in south-east Europe he was arrested and sent to a concentration camp, but survived to be captured by United States authorities.

[3] In the inter-war period he reached the rank of Gruppenführer (major general) in the National Socialist Flyers Corps (German: Nationalsozialistisches Fliegerkorps, NSFK) which was a paramilitary Nazi Party organisation similar to the Sturmabteilung or SA.

[3] With the assistance of his close friend[5] Reichsmarshall Hermann Göring he obtained shares in a range of mining and metal industries through dubious transactions.

Soon after the military administration began, Neuhausen appointed commissioners through whom he controlled the Serbian National Bank and other key economic and financial enterprises.

[13] Neuhausen was a powerful figure who had complete control of the economy and state finances of the occupied territory, and successfully exploited them to make a significant contribution to the German war effort.

In particular, he strenuously opposed attempts by Foreign Affairs Envoy Hermann Neubacher to give more power to the Belgrade puppet government of Milan Nedić.

[13][17] After being captured by US forces he was handed over to the Yugoslav authorities at the end of the war, and although sentenced to 20 years imprisonment following a trial in October 1947, he was soon paroled,[1] then released in March 1953.