Who was responsible for the concept of the separation of church and state or religion and government?

The concept of the separation of church and state is often attributed to Enlightenment thinkers, particularly John Locke, who argued for religious tolerance and the need to limit governmental power over individual beliefs. In the United States, Thomas Jefferson famously articulated this principle in his 1802 letter to the Danbury Baptists, emphasizing the importance of a "wall of separation" between religion and government. This idea was further reinforced by the First Amendment of the U.S. Constitution, which prohibits the establishment of religion by the government.