When I was kid, the phrase “Banned in Boston” confused me. I thought of Boston as a liberal, cosmopolitan city. Surely they didn’t censor things there.

They don’t anymore, but they sure used to. About 100 years ago, Boston was in the grip of dour “vice” crusaders who used their religious beliefs to decide what books and magazines people could read and what performances they could see on stage. And it wasn’t alone.

The American Library Association’s annual “Banned Books Week” kicked off on Sunday. In light of that, it’s a good time to remember the bad old days of religiously based censorship and to celebrate the fact that we’ve overcome them – in most cases.

The controversy over Theodore Dreiser’s 1925 novel An American Tragedy is instructive. Today considered a classic of American realism, the sprawling novel alarmed many religious leaders when it was published because of its central theme: a young, social-climbing man impregnates his working-class girlfriend and, rather than deal with the consequences of his actions, murders her.

Dreiser based his story on an actual incident wrenched from the headlines. His main character, Clyde Griffiths, is based on Chester Gillette, who in 1906 took his pregnant girlfriend out on a lake in New York’s Adirondack Mountains, hit her with a tennis racket and left her to drown.

Boston’s religious leaders were up in arms over the book – oddly, not so much because of its portrayal of murder; rather, many of them were convinced that the book was an endorsement of birth control! (After all, had the young couple used contraceptives, things might have turned out differently.)

Donald Friede, co-owner of Dreiser’s publisher, was duly hauled into court. As W.A. Swanberg points out in his massive biography of Dresier, the members of the jury hadn’t read the book. The prosecutor was permitted to read a few choice excerpts that were deemed “immoral,” but the defense wasn’t allowed to put the book into context by reading other passages.

The prosecuting attorney, Frederick Doyle, invoked “those good Puritans who left England [and] brought with them the innate feelings and instincts of decency.” He blasted the book for harboring “the most disgusting, the most filthy, the most vicious, the most devilish language that a human being could think of.” (I doubt Doyle read the book. There are no sex scenes in it. Dresier alludes to an “intimate relationship” between Griffiths and his girlfriend. That’s it.)

The jury, largely Catholic, was quick to convict. Friede was slapped with a $300 fine, and for some time it wasn’t possible to buy a copy of An American Tragedy in Boston.

A bitter Dreiser later wrote to a friend, “Personally, I am convinced that this is a direct attempt on the part of the officials of the Catholic Church, with possibly the cooperation  of…other denominations.”

Dreiser was right. Boston’s anti-vice movement was led and supported by Catholic clergy and laypeople, in conjunction with conservative Protestants. For many years, they had the power to determine what people in that city could read. If a book offended the clerics' religious sensibilities, people had to go to another town to buy a copy.

Dreiser, though, had the last laugh. An American Tragedy outlived the censors. It was a bestseller upon publication and has remained a popular title. In 2003, the Library of America issued a new edition, cementing the book’s reputation as an exemplary work of American letters.

It has been a long time since the nation experienced a high-profile censorship battle such as the one that enveloped An American Tragedy. But that doesn’t mean the censors have gone away. Indeed, their efforts these days are often focused on public schools, and the books they target are usually titles aimed at young adults.

They aren’t just attacking books; they’re also attacking the freedom to learn, the freedom of a young person to expand his/her horizons and the freedom to be intellectually curious.

Make no mistake, there are people out there who believe they know better than you what books you and your children should be able to read. Luckily, there’s an easy (and enjoyable) way to fight back against them: Read a banned book.