Many lynchings were the result of Southern whites' extrajudicial efforts to maintain white supremacy, after gaining disfranchisement of most blacks through discriminatory voter registration and electoral rules, and imposing segregation and Jim Crow laws on the black population in the late 19th and early 20th century. Maintaining white supremacy in economic affairs played a part as well. Social changes resulting from a rapid rise in immigration from southern and eastern Europe, the rise of the Second Ku Klux Klan, and the internal Great Migration of blacks from the South to industrial cities in the Northeast and Midwest contributed to violent confrontations. In 1917, white mobs had attacked blacks in East St. Louis (a city located directly across the Mississippi River from St. Louis, Missouri) over competition for work and punishment for strikebreakers.