Answer the following question: Given the following passage  "Detroit remains one of the most racially segregated cities in the United States. From the 1940s to the 1970s a second wave of Blacks moved to Detroit to escape Jim Crow laws in the south and find jobs. However, they soon found themselves excluded from white areas of the city—through violence, laws, and economic discrimination (e.g., redlining). White residents attacked black homes: breaking windows, starting fires, and exploding bombs. The pattern of segregation was later magnified by white migration to the suburbs. One of the implications of racial segregation, which correlates with class segregation, may be overall worse health for some populations.",  answer the following question. Note that the answer is present within the text.  Question: Prior to relocating, Blacks were excluded due to what?
Answer:
Jim Crow laws