A “Southern heritage” group is planning a celebration in Montgomery, Ala., that will feature a parade down the city’s historic Dexter Avenue. That’s the same street where thousands of civil rights marchers rallied in support of voting rights at the culmination of the historic Selma-to-Montgomery march in 1965. And it’s the same street where Dr. Martin Luther King, Jr. helped ignite the movement a decade earlier from his pulpit inside the small Baptist church, which still sits in the shadow of the state Capitol.

But the Sons of Confederate Veterans, the group sponsoring the Feb. 19 event, isn’t interested in commemorating King or the civil rights march. Instead, it will celebrate the 150th anniversary of the beginning of the Confederacy. These “sons” plan to reenact the swearing-in of Jefferson Davis as the president of the Confederate States of America and fire off a few cannons to ensure that “the Heritage of the Confederacy…is remembered and portrayed in the right way.”

The right way. Whatever can they mean?

The Civil War was the most devastating conflict in our nation’s history. At least 620,000 soldiers died, as did some 400,000 civilians. Hundreds of thousands of others suffered horrible amputations and terrible wounds. Over four years, the war cost $2.5 million daily – an incredible amount at the time. In the end, the South was laid waste; its industries, grand homes, roads and farms largely destroyed. It would be a century before the region fully recovered. Yes, it was a splendid little war.

Many other celebrations around the South will follow Montgomery’s anniversary bash to mark the sesquicentennial of various milestones in the war that began with the Confederate attack on Fort Sumter on April 12, 1861.

As these events unfold, we’ll hear a lot of revisionist history about the causes of secession – that it wasn’t really about slavery but rather about the defense of “states’ rights,” tariff disputes, or resisting the imposition of northern industrial capitalism. Michael Givens, the head of the Sons of Confederate Veterans, told The New York Times that “our people were only fighting to protect themselves from an invasion and for their independence.”

This idea resonates strongly today among many white Southerners, particularly in this era of tea party politics and radical, anti-government sentiment that has sparked a resurgence of armed militia groups.

But it’s wrong.

Freeing the slaves may not have been Lincoln’s original intent, but it became a major aim of the war, as any serious student of Civil War history knows. And the right to own slaves was, most certainly, the primary reason the Southern states seceded from the Union.

Southern politicians in early 1861 made that perfectly clear. The Texas Declaration of Causes of Secession, for example, explained that the free states were “proclaiming the debasing doctrine of equality for all men, irrespective of race or color,” adding that blacks were “rightfully held and regarded as an inferior and dependent race.” Mississippi’s declaration talks about little but slavery. Its second sentence reads: “Our position is thoroughly identified with the institution of slavery – the greatest material interest of the world.”

Alexander Stephens, vice president of the Confederacy, put it like this in 1862, during his infamous “Cornerstone” speech, “Our new government is founded upon exactly the opposite idea; its foundations are laid, its cornerstone rests, upon the great truth that the negro is not equal to the white man; that slavery – subordination to the superior race – is his natural and moral condition.”

There’s no real question about these historical facts. Events celebrating secession, therefore, are effectively glorifying the South’s defense of slavery and the white supremacist doctrine that underpinned it. They will undoubtedly offend millions of Americans, and rightfully so. But more damaging is the continuing dissemination of false propaganda that does nothing but prevent an entire region from coming to grips with its history, even after 150 years.

Mark Potok is director of the Intelligence Project at the Southern Poverty Law Center, a civil rights organization based in Montgomery, Ala. This article was distributed by Other Words, a project of the Institute for Policy Studies.