Rhode Island was founded to be a haven primarily for New Englanders like the Anabaptists and Quakers, who were unwelcome in the Puritan-ruled enclaves of Connecticut, Massachusetts Bay and Plymouth Plantation. It was the first American colony founded on the principle of separation of church and state.
Roger Williams, the founder of Rhode Island, had been banished from Massachusetts Bay Colony because of his outspoken criticism of the colony's Puritan leadership, effectively a de facto theocracy, as well as his disagreement with the colony's confiscation of Native American land. In 1636, only five years after he had arrived in the New World, the Narragansett tribe helped him establish a small settlement in the unclaimed and unsettled Rhode Island.
When Williams had a settlement organized, he announced that those unhappy with the church-colonial government partnership as practiced in nearby colonies were welcome to join him. Disaffected Puritans, Quakers, Anabaptists and even Jews came to join him in his new town, which he named "Providence." His most famous new neighbor was Anne Hutchinson, who had been exiled from Massachusetts because she was scandalously preaching the Gospel when Puritanism expressly forbade women from preaching.
Rhode Island's independent beginning led to a particularly freedom-loving and somewhat contrarian culture. This colony was the first to renounce British allegiance, the last to sign off on the U.S. Constitution and the first to institute gradual emancipation of slaves.