[1] It was substantially caused by poor economic and social conditions due to prevalent racial segregation and discrimination in the Southern states where Jim Crow laws were upheld.

[14] In 1991, Nicholas Lemann wrote: The Great Migration was one of the largest and most rapid mass internal movements in history—perhaps the greatest not caused by the immediate threat of execution or starvation.

Dubbed the New Great Migration, these moves were generally spurred by the economic difficulties of cities in the Northeastern and Midwestern United States, growth of jobs in the "New South" and its lower cost of living, family and kinship ties, and lessening discrimination.

Some factors pulled migrants to the north, such as labor shortages in northern factories brought about by World War I, resulting in thousands of jobs in steel mills, railroads, meatpacking plants, and the automobile industry.

[20] Northern companies offered special incentives to encourage Black workers to relocate, including free transportation and low-cost housing.

The southern sharecropping system, an agricultural depression, the widespread infestation of the cotton boll weevil, and flooding also provided motivation for African Americans to move into the Northern Cities.

Because changes were concentrated in cities, which had also attracted millions of new or recent European immigrants, tensions rose as the people competed for jobs and scarce housing.

Cities that were affected by the violence included Washington D.C., Chicago, Omaha, Knoxville, Tennessee, and Elaine, Arkansas, a small rural town 70 miles (110 km) southwest of Memphis.

[30]: 22 The Great Depression wiped out job opportunities in the northern industrial belt, especially for African Americans, and caused a sharp reduction in migration.

In the 1930s and 1940s, increasing mechanization of agriculture virtually brought the institution of sharecropping that had existed since the Civil War to an end in the United States causing many landless Black farmers to be forced off of the land.

With the defense buildup for World War II and with the post-war economic prosperity, migration was revived, with larger numbers of Black Americans leaving the South through the 1960s.

This wave of migration often resulted in overcrowding of urban areas due to exclusionary housing policies meant to keep African-American families out of developing suburbs.

Western cities such as Los Angeles, San Francisco, Oakland, Phoenix, Denver, Seattle, and Portland also attracted African Americans in large numbers.

In her book The Warmth of Other Suns, Pulitzer Prize–winning journalist Isabel Wilkerson discusses the migration of "six million Black Southerners [moving] out of the terror of Jim Crow to an uncertain existence in the North and Midwest.

"[38] The struggle of African-American migrants to adapt to Northern cities was the subject of Jacob Lawrence's Migration Series of paintings, created when he was a young man in New York.

[39] Exhibited in 1941 at the Museum of Modern Art, Lawrence's Series attracted wide attention; he was quickly perceived as one of the most important African-American artists of the time.

Great Delta-born pianist Eddie Boyd told Living Blues magazine, "I thought of coming to Chicago where I could get away from some of that racism and where I would have an opportunity to, well, do something with my talent....

[citation needed] Educated African Americans were better able to obtain jobs after the Great Migration, eventually gaining a measure of class mobility, but the migrants encountered significant forms of discrimination.

Because so many people migrated in a short period of time, the African-American migrants were often resented by the urban European-American working class (many of whom were recent immigrants themselves); fearing their ability to negotiate rates of pay or secure employment, the ethnic whites felt threatened by the influx of new labor competition.

Mortgage discrimination and redlining in inner city areas limited the newer African-American migrants' ability to determine their own housing, or obtain a fair price.

[54] Migrants going to Albany, New York found poor living conditions and employment opportunities, but also higher wages and better schools and social services.

Local organizations such as the Albany Inter-Racial Council and churches, helped them, but de facto segregation and discrimination remained well into the late 20th century.

[56][57] Historian Joe Trotter explains the decision process: Although African-Americans often expressed their views of the Great Migration in biblical terms and received encouragement from northern Black newspapers, railroad companies, and industrial labor agents, they also drew upon family and friendship networks to help in the move to Western Pennsylvania.

In barbershops, poolrooms, and grocery stores, in churches, lodge halls, and clubhouses, and in private homes, Black people who lived in the South discussed, debated, and decided what was good and what was bad about moving to the urban North.

"The foundation of the first African American YMCA took place in Bronzeville, and worked to help incoming migrants find jobs in the city of Chicago.

"[64] When the Great Migration started in the 1910s, white southern elites seemed to be unconcerned, and industrialists and cotton planters saw it as a positive, as it was siphoning off surplus industrial and agricultural labor.

As the migration picked up, however, southern elites began to panic, fearing that a prolonged Black exodus would bankrupt the South, and newspaper editorials warned of the danger.

Large numbers of poor whites from Appalachia and the Upland South made the journey to the Midwest and Northeast after World War II, a phenomenon known as the Hillbilly Highway.

This rise in net gain points to Atlanta, Charlotte, Dallas, and Houston being a growing hot spots for the migrants of The New Great Migration.

Other southern states, including Mississippi, Louisiana, South Carolina, Alabama and Arkansas, have seen little net growth in the African-American population from return migration.