On 9 November 1938 , the Nazi government of Germany began open war against its Jewish citizens with the pogrom known as Kristallnacht , with over a thousand synagogues damaged or destroyed , thousands of Jewish businesses damaged , 30,000 Jews arrested and at least 91 Jews murdered . On 1 September 1939 , Nazi Germany invaded Poland , home at that time to the largest Jewish community in the world , precipitating the start of World War II . Salazar reacted by sending a telegram to the Portuguese Embassy in Berlin ordering that it should be made clear to the German Reich that Portuguese law did not allow any distinction based on race , and therefore Portuguese Jewish citizens could not be discriminated against
Kristallnacht
Kristallnacht
Aristides de Sousa Mendes