Roger Williams was a 17th-century English theologian, minister, and political leader who established the Providence Plantations in New England. Born in London around 1603, he eventually emigrated to America, where his evolving religious views led to his expulsion from the Massachusetts Bay Colony. He became a prominent advocate for the separation of church and state and the principle of religious liberty. Through his founding of Rhode Island, he created one of the first governments to guarantee freedom of conscience, a concept that later influenced American constitutional principles.