By 1940, U.S. rearmament and defense contracting were accelerating, creating new industrial jobs in northern and western cities. These labor demands helped restart large-scale movement out of the Jim Crow South after Depression-era slowdowns. This context set the stage for the Second Great Migration.
Beginning in the early 1940s and continuing for decades, millions of African Americans moved from the South to the Northeast, Midwest, and especially the West. Many migrants were leaving southern towns and cities for industrial and defense work, not only farming. This shift reshaped the population of cities such as Los Angeles, Oakland, Detroit, Chicago, and New York.
On June 25, 1941, President Franklin D. Roosevelt issued Executive Order 8802, which prohibited racial discrimination in the defense industry and created the Fair Employment Practice Committee (FEPC). The order mattered because it improved access to better-paying wartime jobs, strengthening the pull of northern and western cities for Black workers. It was also an early federal step toward stronger civil-rights enforcement later on.
From June 20–22, 1943, Detroit experienced a major racial riot during a period of rapid wartime population growth. The city’s auto plants had been converted to war production, drawing large numbers of migrants and intensifying competition for housing and jobs. Events like this showed how overcrowding and discrimination in destination cities shaped daily life for many new arrivals.
After World War II, federal benefits such as low-cost home loans and education assistance helped many veterans build wealth and move to new neighborhoods. In practice, Black veterans often faced barriers through segregated or discriminatory local administration, as well as redlining and unequal lending. These limits shaped where many migrant families could live, often reinforcing crowded urban neighborhoods.
On July 26, 1948, President Harry S. Truman signed Executive Order 9981, directing equality of treatment and opportunity in the U.S. armed services. The order was significant because it expanded federal action against segregation and helped train and employ Black service members in new roles. Military service and postwar job networks also influenced migration choices and opportunities.
On May 17, 1954, the U.S. Supreme Court ruled in Brown v. Board of Education that segregation in public schools violated the Constitution. Although implementation was slow and often resisted, the decision helped weaken the legal foundations of Jim Crow. For many families, it also signaled that national civil-rights change was possible, even as southern conditions still pushed migration.
From December 5, 1955 to December 20, 1956, Montgomery’s Black community sustained a boycott of segregated city buses. The boycott ended after court rulings struck down bus segregation, and it elevated nonviolent mass protest as a key civil-rights strategy. Organizing victories like this helped connect southern communities to a growing national movement during the migration era.
On June 29, 1956, the Federal-Aid Highway Act created the Interstate Highway System. New highways made suburban growth easier and changed how people and goods moved in metropolitan areas. In many cities, highway construction also disrupted established neighborhoods, adding another layer to the housing pressures migrants faced.
The Civil Rights Act took effect on July 2, 1964, prohibiting discrimination in public accommodations and employment (among other provisions). The law mattered to migration because jobs and public life in many destination cities were central reasons people moved. It also shifted expectations about federal enforcement, even while local inequality persisted.
On August 6, 1965, President Lyndon B. Johnson signed the Voting Rights Act into law, targeting barriers such as literacy tests. Expanded voting access increased Black political influence in the South and affected national politics. Over time, stronger voting rights also changed how some migrants weighed staying, returning, or moving again within the U.S.
From August 11–16, 1965, the Watts neighborhood of Los Angeles saw a major uprising after an arrest, amid long-standing grievances about policing, jobs, housing, and poverty. The event showed that moving west for work did not mean escaping segregation or discrimination. It also drew national attention to racial inequality in fast-growing urban areas shaped by migration.
Beginning July 23, 1967, Detroit experienced one of the most severe urban uprisings of the era, rooted in long-standing tensions over policing, discrimination, and economic opportunity. The scale of violence and destruction amplified debates about inequality in northern industrial cities that had drawn many southern migrants. It also helped push federal leaders to study the deeper causes of civil disorder.
On February 29, 1968, the National Advisory Commission on Civil Disorders (the Kerner Commission) issued its final report. It argued that discrimination, poverty, and unequal opportunity were central drivers of unrest, and it urged major investments in jobs, housing, and education. The report summarized how the gains of migration and civil-rights laws were being limited by segregation and economic inequality in many cities.
On April 11, 1968, President Johnson signed the Civil Rights Act of 1968, including the Fair Housing Act. The law aimed to reduce discrimination in housing—a key issue in many destination cities where migrants faced exclusion from suburbs and better-resourced neighborhoods. It marked a major policy response to the housing bottlenecks that had shaped the Second Great Migration’s urban footprint.
By 1970, the Census Bureau’s decennial census captured the end of the 1940–1970 “Second Great Migration” phase used in many demographic summaries. Over these decades, large numbers of Black southerners relocated to urban centers across the Northeast, Midwest, and West, reshaping U.S. city populations. Around this point, net out-migration from the South slowed and patterns began to change, setting up later “return” migration trends.
Second Great Migration (1940–1970)