This paper aims to reveal how religiousness is in the United States based on the ideas of Roger Williams. From various sources, there are three things that form the background of Roger Williams thinking. Those are when he was in England, where the seekers of truth burned alive in frontof his house, the indication of churches dominating on the people’s life and the using of their force on one’s beliefs; his acquaintance with the Indians who taught him that anyone can say honestly without having to swear in the name of the holy book, and that anyone can help eachother without having or within one belief. Religiousness in America in terms of the thinking of Roger Williams is that the people have freedom to show their belief through both deeds and symbols as long as it does not annoy the others. The good and tolerant deeds are actually neededin a multicultural society. Religiousness means someone more aware of his choice in choosing a belief; his worship to the Lord was not as something imposed because of the control of the authorities.