 As nuncio during the 1920s , he had made unsuccessful attempts to obtain German agreement for such a treaty , and between 1930 and 1933 he attempted to initiate negotiations with representatives of successive German governments , but the opposition of Protestant and Socialist parties , the instability of national governments and the care of the individual states to guard their autonomy thwarted this aim . In particular , the questions of denominational schools and pastoral work in the armed forces prevented any agreement on the national level , despite talks in the winter of 1932 . 
