1917. In 1918 he returned to the mountains when he was transferred to Armeegruppe Tirol, and ended the war as an Oberstleutnant (lieutenant colonel) and chief quartermaster for the entire Alpine Front. Between the wars After the war the Austro-Hungarian Empire was dissolved, and Phleps returned to his homeland, which had become part of the Kingdom of Romania under the Treaty of Trianon. He joined the Romanian Army and was appointed commander of the Saxon National Guard, a militia formed of the German-speaking people of Siebenbürgen. In this role he opposed the Hungarian communist revolutionary government of Béla Kun, which fought against Romania in 1919. During a battle at the Tisza river against Kun's forces, Phleps disobeyed direct orders and was subsequently court-martialled. The trial concluded that he had saved the Romanian forces through his actions, and he was promoted to Oberst (colonel). He commanded the 84th Infantry Regiment, then joined the general army headquarters and started teaching logistics at the Romanian War Academy in Bucharest. He attended the V Army Corps staff college in Brașov, and published a book titled Logistics: Basics of Organisation and Execution in 1926, which became the standard work on logistics for the Romanian Army. Ironically, after the book was published, Phleps failed his first general's examination on the topic of logistics. He commanded various Romanian units, including the 1st Brigade of the vânători de munte (mountain ranger troops), while serving also as a military advisor to King Carol II in the 1930s. Phleps reached the rank of General-locotenent (major general) despite his reported disdain for the corruption, intrigue and hypocrisy of the royal court. After criticising the government's policy and publicly calling King Carol a liar when another general tried to twist his words, he was transferred to the reserves in 1940 and finally dismissed from service at his own request in 1941. World War II SS Motorised Division Wiking In November 1940, with the support of the leader of the Volksgruppe in Rumänien (ethnic Germans in Romania), Andreas Schmidt, Phleps wrote to the key Waffen-SS recruiting officer SS-Brigadeführer und Generalmajor der Waffen SS (Brigadier) Gottlob Berger offering his services to the Third Reich. He subsequently asked for permission to leave Romania to join the Wehrmacht, and this was approved by the recently installed Romanian Conducător (leader), the dictator General Ion Antonescu. Phleps volunteered for the Waffen-SS instead, enlisting under his mother's maiden name