How was social Darwinism used to support imperialist and racist policies?

Social Darwinism, a theory popularized by the British philosopher Herbert Spencer, applied the concept of "survival of the fittest" to human societies. This framework was used to provide a pseudoscientific rationalization for imperialist, colonialist, and racist policies during the late 19th and early 20th centuries.123

By framing societies as organisms engaged in a constant struggle for existence, proponents argued that powerful nations were inherently superior and destined to dominate those they deemed "unfit" or "savage". This ideology supported the following:14

• Justification for Expansion: Imperial powers viewed the conquest of overseas territories as a natural outcome of biological competition, where nations that failed to expand risked sinking into obscurity.3
• Racial Hierarchy: It sustained beliefs in the biological and cultural superiority of specific groups, such as Anglo-Saxon or Aryan peoples, often using "vulgar anthropology" to rank races based on physical traits.13
• Opposition to Reform: Because social Darwinists believed that the "fittest" should naturally prevail, they opposed state intervention, charity, and social welfare, arguing these interfered with the necessary laws of natural evolution.14

Ultimately, this ideology fostered a climate of bellicosity and fatalism, eroding the moral and political restraints that had previously discouraged conflict between nations.3