After the war, Philipp enlisted in the "Übergangsheer" (the Transitional Army) which was successful in repressing communist and socialist action. From 1920 to 1922, he attended the Technical University in Darmstadt where he studied art history and architecture. He made several visits to Greece where his aunt Princess Sophie of Prussia was the wife of King Constantine I. In 1922, he left university without completing a degree and took a job at the Kaiser-Friedrich-Museum in Berlin. The following year, he moved to Rome where he used his aristocratic connections to establish himself as a successful interior designer. (He had designed some furniture for the palace his father intended to occupy as King of Finland.)