The historical figure best known for promoting the Theory of Evolution is Charles Darwin. His seminal work, "On the Origin of Species," published in 1859, introduced the concept of natural selection as the mechanism of evolution. Darwin's ideas challenged traditional beliefs about creation and sparked significant debate within both scientific and religious communities. The theory posited that species evolve over time through a process of adaptation to their environment, leading to the development of new species. Darwin's research laid the groundwork for the field of evolutionary biology.