The story, at first glance, seems harmless, at least by today’s standards.

It opens on the Arthur Shelby plantation in Kentucky as two enslaved people, Tom and 4-year old Harry, are sold to pay Shelby family debts. We then shift focus onto two protagonists; Tom, a strong, religious man living with his wife and three young children, and Eliza, Harry’s mother, whose husband George has already escaped to the north, planning on saving up enough money to buy his family’s freedom.

From there, it ventures into a tale of two destinies. Eliza runs away, making a dramatic escape over the frozen Ohio River with Harry in her arms. Eventually the Harris family is reunited and journeys north to Canada. Tom, on the other hand, chooses to stay, believing he is best protecting his family by doing so. His years of suffering at the hands of his various masters are endured by his deep Christian faith, which he shares with a rotating cast of characters.

The novel ends when both Tom and Eliza escape slavery: Eliza and her family reach Canada, but Tom’s freedom only comes in death. Simon Legree, Tom’s latest master, has Tom whipped to death for refusing to deny his faith or betray the hiding place of two fugitive women. As Tom is dying, he forgives the overseers who savagely beat him. Humbled by the character of the man they have killed, both men become Christians. George Shelby, Arthur Shelby’s son, arrives to buy Tom’s freedom, but Tom dies shortly after they meet.

It’s a heartbreaking yet uplifting story, a history lesson for modern audiences as they remember the evils of an era long-since past.

It was a whole different thing to read it when slavery was not yet a national shame but a very real and very current way of life.

The book, of course, was Uncle Tom’s Cabin, published back on this day in 1852. Although public outrage and protests against slavery had been growing for some time, the Civil War–and thus, slavery’s abolition–was still years in the future. However, Harriet Beecher Stowe, the book’s author, was determined to do what she could to speed the wheels of history.

Stowe was born in 1811, the seventh child of the famous Congregationalist minister Lyman Beecher. She studied at private schools in Connecticut, then taught in Hartford from 1827 until her father moved to Cincinnati in 1832. Cincinnati’s trade and shipping business on the Ohio River was booming, drawing numerous migrants from different parts of the country, including many escaped slaves, bounty hunters seeking them. During this time, Beecher met a number of African Americans who had suffered in slavery and its aftermath; the tales haunted her, firmly solidifying her abolitionist stance. In 1836, she married Calvin Ellis Stowe, with whom she had seven children while also continuing to teach and pursue her true passion: writing stories and essays. She published her first book, Mayflower, in 1843.

Then, on September 18, 1850, the U.S. Congress passed the Compromise of 1850. Among its provisions was creation of the Fugitive Slave Law. Although helping those who escaped slavery had been illegal since 1793, the new law required that everyone, including ordinary citizens, help catch alleged fugitives. Those who aided escapees or refused to assist slave-catchers could be fined up to $1,000 and jailed for six months.

Stowe was furious. She believed slavery was unjust and immoral, and bristled at an law requiring citizen — including her — complicity. Living in Brunswick, ME, while her husband taught at Bowdoin College, Stowe disobeyed the law by hiding John Andrew Jackson, who was traveling north from enslavement in South Carolina. When she shared her frustrations and feelings of powerlessness with her family, her sister-in-law Isabella Porter Beecher suggested she do more: “…if I could use a pen as you can, Hatty, I would write something that would make this whole nation feel what an accursed thing slavery is.”

On March 9, 1850, Stowe wrote to Gamaliel Bailey, editor of the weekly anti-slavery journal The National Era, that she planned to write a story about the problem of slavery: “I feel now that the time is come when even a woman or a child who can speak a word for freedom and humanity is bound to speak … I hope every woman who can write will not be silent.”

Shortly after in June 1851, when she was 40, the first installment of Uncle Tom’s Cabin was published in serial form in the journal. Although Beecher had originally only planned to write three or four installments of the story, it soon grew to more than 40, as she pulled from testimonies she had gathered from both the slaves she encountered in her time in Cincinnati as well as those she helped in the Underground Railroad. Originally titled “The Man That Was a Thing”, it was soon changed to “Life Among the Lowly,” with installments published weekly from June 5, 1851, to April 1, 1852. It was so popular, the entirety of the story was published in a two-book volume under the name Uncle Tom’s Cabin on March 20, 1852 by John P. Jewett with an initial print run of 5,000 copies.

It immediately created waves.

An instant bestseller, the book sold an astonishing 10,000 copies in the United States in its first week; by the end of its first year, that number had risen to an unprecedented 300,000. In the 19th century, the only book to outsell Uncle Tom’s Cabin was the Bible.

It seemed everyone everywhere was reading Beecher’s novel.

And they had opinions.

As expected, white people in the south were outraged. Southern novelist William Gilmore Simms declared the work utterly false while also calling it slanderous. Violent mobs and mailbag burning–when it was thought to contain abolitionist literature–were not uncommon during this time. There were even reporters that a bookseller in Mobile, Alabama, was forced to leave town for selling the novel. Stowe herself received death threats, including a package containing a slave’s severed ear.

But criticism didn’t just come from slavery’s proponents.

Frederick Douglass was “convinced both of the social uses of the novel and of Stowe’s humanitarianism” and heavily promoted the novel in his newspaper during the book’s initial release. Though Douglass said Uncle Tom’s Cabin was “a work of marvelous depth and power,” he also published criticism of the novel, most prominently by Martin Delany. In a series of letters in the paper, Delany accused Stowe of “borrowing (and thus profiting) from the work of black writers to compose her novel” and chastised Stowe for her “apparent support of black colonization to Africa.”

Other readers questioned Stowe’s authority to write Uncle Tom’s Cabin. She was a Northern white woman writing an exposé of slavery, and people from the 19th century until today have questioned whether she had the ability or right to speak for people of African descent. Though Stowe was earnest in her attempts to portray slavery as it really was—gathering an impressive array of facts, figures, and first-person testimonies to supplement her own observations—she would not have had the same insight or understanding as an enslaved person experiencing those conditions. Her reliance on racial stereotypes exposed her misconceptions about Black people, discrediting her authority even more.

Despite these complications and criticisms, the novel’s impact cannot be understated. Stowe’s position as a white author meant that she had access to larger audiences, and so, even though some doubted her perspective, she was able to reach and influence more people with her powerful argument against slavery. In spite of the threat of violent persecution, and her expected role as a respectable woman, Stowe put pen to paper, illustrating slavery’s effect on families and helping readers empathize with enslaved characters. In fact, many readers were forced to recognize the humanity of black slaves for the first time. With this, the outrage against the institution continued to grow, culminating in a vicious Civil War that marked the end of this sad era in American history.

Such was the novel’s impact that legend says that when President Abraham Lincoln met Stowe in 1862, he reportedly said, “So this is the little lady who made this big war.”