The reorganization of occupied dioceses during World War II was an issue faced by Pope Pius XII of whether to extend the apostolic authority of Catholic bishops from Nazi Germany and Fascist Italy to German-occupied Europe during World War II.
Although such reorganization was often refused, the decision of Pius XII to appoint German apostolic administrators to occupied Poland was "one of his most controversial decisions". These actions were the primary justification given by the Soviet-backed Polish Provisional Government (which replaced the pro-Catholic Polish government-in-exile), for declaring the Concordat of 1925 null and void in 1945, an act that had tremendous consequences for post-war Polish-Holy See relations. There was no Apostolic Nuncio to Poland between 1947 and 1989.
A note from Reich ambassador to the Holy See, Diego von Bergen, dated 29 August 1941 demanded that "all ecclesiastical appointments to important posts in annexed or occupi