In early 1919, following the events in Berlin, Strachwitz returned to his home estate, where he found his family palace had been taken over by French officers. Upper Silesia was occupied by British, French and Italian forces, and being governed by an Inter-Allied Committee headed by a French general, Henri Le Rond. The Versailles Treaty at the end of World War I had shifted formerly German territory into neighbouring countries, some of which had not existed at the beginning of the war. In the case of the new Second Polish Republic, the Treaty detached some of territory, which had formerly been part of the German Empire, to recreate the country of Poland, which had disappeared as a result of the Third Partition of Poland in 1795. His father urged him to prepare and educate himself in order to take over the family estate and business. He was put under the guidance of his father's "Oberinspektor" (Chief Inspector). At the same time, Strachwitz, fearing that Silesia was being "handed over to the Poles", as he viewed the actions of the Inter-Allied Committee, joined the "Oberschlesischer Selbstschutz" (Upper Silesian Self Defence). Strachwitz collected weapons and recruited volunteers, which was prohibited. He was caught four times and put in prison in Oppeln by the French. His father was also imprisoned for his opposition to the Inter-Allied Committee. Roll states that Strachwitz's distrust for the French, rooted in his experiences as a prisoner of war during World War I, was immense. He believed that only the Italians had played an honest and neutral role in the occupation of Upper Silesia. On 25 July 1919, he married Alexandrine Freiin Saurma-Jeltsch, nicknamed "Alda", and their first child, a son, was born on 4 May 1920.