The Black Population in the US in 1900 vs 2020

IllustriousDudeIDK:

The large shift was due to the Great Migration, where Black Southerners left/fled the South to seek better living and working conditions in the North and West (usually in cities). This largely started in the 1910s (around WW1, when there was a high demand for workers) and ended around the 1970s (the decade after the Civil Rights Acts and Voting Rights Act). 

Accreditation to Tweedle for 1900 and 2020 maps

Collection: ethnic-groups - Tags: african-americans, us - Source: reddit.com