The Hart–Celler Act reshapes American Islam

The Immigration and Nationality Act of 1965 abolishes the national-origins quota system that had restricted immigration from outside Western Europe since the 1920s. Students, physicians, and engineers from South Asia, the Middle East, and Africa build new Muslim communities from Houston to Chicago.

Signed by President Johnson at the base of the Statue of Liberty on October 3, 1965, the law is the single largest structural cause of American Islam's modern diversity: the demographic turn behind most of the map's 'Communities today' layer.