Final answer:
The correct historical event associated with African-American movement is the Exodusters migration, with around 20,000 migrants moving to Kansas, not over a million. A larger movement, the Great Migration, involved 350,000 African Americans moving North from 1910 onwards, with more than half a million living west of the Mississippi by 1890.
Step-by-step explanation:
The statement that 'By 1910, over a million African-American homesteaders had resettled to the Great Plains' is not accurate according to historical records. The actual movement, known as the Exodusters migration, involved approximately 20,000 Southern black migrants who moved chiefly to Kansas and other parts of the West seeking political, legal, and economic freedom post-Reconstruction. These migrants faced significant opposition from both Southern whites, who were concerned about losing their labor force, and Northern whites, who opposed black migration to their communities.
During the Great Migration that began around 1910 and continued into the 1920s, nearly 350,000 African Americans fled the South for Northern urban centers, seeking better work and living conditions. By 1920, the numbers of African American women employed in manufacturing industries had grown substantially. Additionally, by 1890 over 500,000 Black Americans lived west of the Mississippi River and some worked as cowboys or 'Buffalo Soldiers', contributing to the expansion and protection of the Western frontier.