Born in London in 1603, Roger Williams grew up in an era of religious conflict and persecution. By the time he had completed his university studies, Roger Williams had already embraced the dangerous idea of freedom of worship.

Williams became an outspoken and controversial Puritan minister. Like many of those who came to Plymouth Colony in the 1620s and '30s, he was a Separatist, who believed that Puritans must break with the Church of England. His Separatism as well as his unorthodox ideas on freedom of worship got him into trouble with church officials, and he fled England to avoid arrest.

Arriving in Boston in 1630, Roger Williams was warmly received as a "godly minister." But word soon spread of his radical ideas, and he moved on to Plymouth, which was more hospitable than Boston to Separatists. After only two years there, he accepted a call to a church in Salem; as soon as he was back in the Bay Colony, his troubles began to multiply.

Having been both a witness to and a victim of religious persecution, Roger Williams believed that most of the wars in the world were the result of religious conflict. He advocated total religious toleration, even as other Puritan ministers preached "Tis Satan's policy, to plead for an indefinite and boundless toleration." Unlike most Massachusetts ministers, Williams did not believe that the Bible demanded punishment of religious heretics. His interpretation of scripture made him a serious threat to the authority of a colonial society that depended on the Bible as a life guide.

Although his Salem congregation embraced his teachings, the ministers and magistrates in the colonial capital did not. Williams' ideas grew even more radical. He argued that "all religious sects had the right to claim equal protection from the laws, and that the civil magistrates had no right to restrain the consciences of men or to interfere with their modes of worship or religious belief." He criticized the Massachusetts Bay clergy for intolerance and autocracy in matters of church governance. He urged his congregation to break openly with the Church of England. When the Puritan authorities in Boston condemned Williams' views as "erroneous and very dangerous," he called on his Salem church to break from all other colonial churches.

Roger Williams' religious views were not the only unusual thing about him. He was one of the few Englishmen in the New World to sympathize with and respect the Native American population. He proposed that the Indians were the legitimate owners of the land, and that colonists should acquire property by purchasing it from the Native People. This view challenged the system under which the British king had granted land in North America to his subjects and stirred resentment among the rulers of the Massachusetts Bay Colony.

A few years after Roger Williams established Providence, he founded the first Baptist church in America there. Providence was open to people of all faiths, and Baptists, Quakers, and Jews found a home in the colony. Williams remained a friend to the Native Americans, and did not try to convert them to Christianity.

In 1644 he published a powerful defense of religious freedom. "To molest any person, Jew or Gentile, for either professing doctrines or practicing worship," he wrote, "is to persecute him . . . Having bought Truth dear we must not sell it cheap, nor the least grain of it for the whole world."