Why did the treatment of the jews change from 1939 to 1945?
The treatment of Jews really changed in 1933 when Hitler rose to power. Concentration camps started a little after that, but the mass movement of Jews into camps really started in 1939 with the onset of WW2. You have to realize that the blatant mistreatment of Jews wasn’t world wide, it was much more concentrated in Germany, and in places controlled by Germany. The main reason the Germans did such horrible things to the Jews was because non-Jewish Germans blamed the Jews for the Great Depression (it was worldwide). Since Europeans have always had a dislike/mistrust of the Jews, it wasn’t hard for them to blame the Jews for the horrible economy. After the Jews became the scapegoat for the Depression, everything went downhill from there.