The 20th Century brought massive waves of immigration around the globe which, in turn, created concerns in most of the receiving countries. In 1917 the United States passed the Emmigration Act of 1917 which imposed literacy tests and taxes on immigrants and banned immigrants deemed “undesirables”—essentially any sick, disabled, or criminal members of society. Restriction soon came to include specific races and ethnicities; all immigrants from a region termed the Asiatic Barred Zone (modern day India, Afghanistan, Iran, Saudi Arabia, Russia, Southeast Asia and the Asian-Pacific islands) were blocked.
A second wave of restrictions, supposedly as an effort to protect the nation from Bolsheviks was passed.
And in 1921 Congress passed the Emergency Quota Act, which set numerical quotas for the number of immigrants coming to the United States. The Johnson-Reed Act of 1924 further reduced the number of allowed immigrants.
Similar measures were taken in Britain with the Aliens Act of 1905 and the Aliens Restriction Act of 1914. Canada followed in 1910 and with a more restrictive act in 1919.
During the German Empire and the Weimar Republic, Germany was one of the countries most sought after by Jews who were leaving eastern, central and south-eastern Europe. The first big wave of Jewish refugees to Germany from the east reached was a result of the civil disturbances in Russian in 1905
During the World War I second wave of Jewish immigrants from the East poured into Germany this wave settled mainly in Central Europe, Germany and Austria. "Hundreds of thousands of Polish Jews fled to Vienna and Berlin: children of foreign culture, speaking a foreign language, upholding foreign customs and beliefs." The historian Anne-Christin Saß discovered that in the second half of the 1920s in Berlin, Jews were prevented from continuing to move further west in Europe or even as far as the US, as they had originally intended; thus Berlin developed into a world Jewish center.
The years after the end of World War I were chaotic with large movements of people flowing into Germany from
Eastern Europe and the dismembered Austro-Hungarian Empire. In 1920, the Bavarian government opened the first immigration detention site in Germany: Fort Prinz Karl in Ingolstadt, about an hour away from Munich. Simultaneously, the Prussian government also opened two immigration detention sites – one in Cottbus in Eastern Germany and one in Stargard in present-day Poland. Who "belonged" in Germany and who should not was as serious a question in 1925 as it is in the
United States today.
Against this background the National Socialist government sought to define who was to have rights and privileges of
German citizenship; passing the Reich Citizenship Law in 1935. The law was simple with two fundamental ideas-
A subject of the state is one who belongs to the protective union of the German Reich, and who, therefore, has specific obligations to the Reich.
and
A citizen of the Reich may be only one who is of German or kindred blood, and who, through his behaviour, shows that he is both desirous and personally fit to serve loyally the German people and the Reich.
https://alphahistory.com/nazigermany/re ... -law-1935/
There was a Supplementary Decree in November 1935 which read
“Article 1. Until further provisions concerning citizenship papers, all subjects of German or kindred blood who possessed the right to vote in the Reichstag elections when the Citizenship Law came into effect, shall, for the present, possess the rights of Reich citizens. The same shall be true of those upon whom the Reich Minister of the Interior, in conjunction with the Deputy to the Fuhrer, shall confer citizenship.
Jewish-Germans were particularly mentioned for protection;
The provisions of Article I shall apply also to subjects who are of mixed Jewish blood.
The legal definition of a "Jew" was restricted
A Jew is an individual who is descended from at least three grandparents who were, racially, full Jews.
https://alphahistory.com/nazigermany/re ... cree-1935/