The founder of the Rhode Island colony was Roger Williams, a dissenter from Massachusetts who had more liberal ideas than some of the Puritan fathers in the Massachusetts Bay colony. Williams first established Providence, which eventually merged with other settlements such as Newport and became the colony of Rhode Island. Williams obtained a charter from Parliament in 1643, which gave the colony the right to govern itself.
Williams believed in the separation of church and state, and thus is a revered figure in the history of American ideas of religious freedom. The colony attracted freethinkers of all kinds, including Anne Hutchinson, who was found guilty of heresy in her famous trial in Massachusetts. Although the government of Rhode Island was not fully democratic, the settlers nevertheless felt free to express themselves in various ways, with the result that Rhode Island was one of the more turbulent colonies.
Because of the conflict between King Charles I and Parliament that led to the English Civil War, Rhode Island's charter was declared invalid following the restoration of Charles II. Rhode Island then got a new charter, which affirmed the rights granted under the first charter and included a land grant. It also declared that people should be free of any sort of persecution "for any difference in opinion in matters of religion." That provision reflected the feelings of Roger Williams himself, and the idea continued to grow as the American colonies developed. So liberal was the religious posture of Rhode Island that Roman Catholics and even Jews were welcome in the colony. Rhode Island remained, however, something of an outcast among the rest of the colonies for its different ways. (Following the American Revolution, Rhode Island was the only state that did not send a delegation to the Constitutional Convention in 1787.) Yet the people of Rhode Island felt strongly about their views and defended their positions against the other New England colonies.