Alabama's population exploded from ~127,000 (1820) to ~964,000 (1860). Six powerful draws:
The Black Belt's rich, dark prairie soil was ideal for long-staple cotton, the era's "white gold." Planters brought enslaved labor to exploit it.
Long growing seasons (200+ frost-free days) and ample rainfall supported cotton, corn, and livestock.
Cheap federal land (via land acts), speculative profits, and a booming cotton economy attracted planters, yeoman farmers, merchants, and speculators.
Alabama entered the Union (1819) as a state with universal white male suffrage—no property qualification—unlike many older states.
No established church; Baptists, Methodists, Presbyterians, and others organized freely, shaping a distinct Southern evangelical culture.
This "opportunity" was built on forced removal of Creek, Choctaw, Cherokee, and Chickasaw nations (Indian Removal Act, 1830s) and the enslavement of nearly 435,000 Black people by 1860. The settlers' gains came at catastrophic human cost.