Who coined the term "Survival of the Fittest" in relation to human societies?

The term "Survival of the Fittest" was coined by Herbert Spencer as he framed it in the context of social theory and human societies. Spencer was influenced by Darwinian evolutionary theory but applied it beyond biological contexts to social and cultural institutions, advocating for the idea that those who are best adapted to their environment, socioculturally speaking, will succeed and dominate. This phrase captures a idea about societal progress and competition, suggesting that societies evolve through a similar process as natural selection in biology. Although often associated with Darwin, who is well-known for his work on natural selection, it was Spencer who specifically introduced this phrase to describe competition within human societies.