We’ve talked about this here many times, but this an excellent article with lots of interesting tidbits to nibble on, so you might want to bookmark it for future reference.

The idea that the United States has always been a bastion of religious freedom is reassuring—and utterly at odds with the historical record

Philadelphia’s Bible Riots of 1844 reflected a strain of anti-Catholic bias and hostility that coursed through 19th-century America. (Granger Collection, New York)

By Kenneth C. Davis
Smithsonian magazine, October 2010

Wading into the controversy surrounding an Islamic center planned for a site near New York City’s Ground Zero memorial this past August, President Obama declared: “This is America. And our commitment to religious freedom must be unshakeable. The principle that people of all faiths are welcome in this country and that they will not be treated differently by their government is essential to who we are.” In doing so, he paid homage to a vision that politicians and preachers have extolled for more than two centuries—that America historically has been a place of religious tolerance. It was a sentiment George Washington voiced shortly after taking the oath of office just a few blocks from Ground Zero.

But is it so?

In the storybook version most of us learned in school, the Pilgrims came to America aboard the Mayflower in search of religious freedom in 1620. The Puritans soon followed, for the same reason. Ever since these religious dissidents arrived at their shining “city upon a hill,” as their governor John Winthrop called it, millions from around the world have done the same, coming to an America where they found a welcome melting pot in which everyone was free to practice his or her own faith.

The problem is that this tidy narrative is an American myth. The real story of religion in America’s past is an often awkward, frequently embarrassing and occasionally bloody tale that most civics books and high-school texts either paper over or shunt to the side. And much of the recent conversation about America’s ideal of religious freedom has paid lip service to this comforting tableau.

From the earliest arrival of Europeans on America’s shores, religion has often been a cudgel, used to discriminate, suppress and even kill the foreign, the “heretic” and the “unbeliever”—including the “heathen” natives already here. Moreover, while it is true that the vast majority of early-generation Americans were Christian, the pitched battles between various Protestant sects and, more explosively, between Protestants and Catholics, present an unavoidable contradiction to the widely held notion that America is a “Christian nation.”

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More: http://www.smithsonianmag.com/history-archaeology/Americas-True-History-of-Religious-Tolerance.html