What economic opportunity drew the most migrants to the

West?

It was land, ultimately, that drew the most migrants to the West. Family farms were the backbone of the agricultural economy that expanded in the West after the Civil War. In 1862, northerners in Congress passed the Homestead Act, which allowed male citizens (or those who declared their intent to become citizens) to claim federally owned lands in the West. Settlers could head west, choose a 160-acre surveyed section of land, file a claim, and begin "improving" the land by plowing fields, building houses and barns, or digging wells, and, after five years of living on the land, could apply for the official title deed to the land. Hundreds of thousands of Americans used the Homestead Act to acquire land. The treeless plains that had been considered unfit for settlement became the new agricultural mecca for land-hungry Americans.

Free unclaimed land and the possibility of discovering gold.