Jerry O. Potter couldn’t believe his eyes. He had studied the Civil War in Tennessee for years, but he’d never heard of the event portrayed in a painting at a local bank. The painting showed dramatic images of a steamship in flames and a river filled with drowning, screaming bodies. In fact, the disastrous Sultana explosion in April 1865 was the United States’ worst maritime disaster—but Potter had never run across the Memphis-area tragedy despite years of study.

He wasn’t alone. Though the disaster killed up to 2,000 people, it’s hardly known today. Few books have been written about Sultana, and it’s rarely commemorated or even mentioned.

Even more amazingly, people barely cared about the disaster when it occurred—it didn’t even make it into many newspapers. Potter, who has obsessively researched the disaster since he first saw that painting in 1978, thinks he knows why.

“You have to start with the fact that it occurred on April 27, 1865,” he says. The disaster took place during one of the most action-packed months in American history. Though the country was technically still at war, Robert E. Leesurrendered to Ulysses S. Grant and Union troops on April 12. Two days later, John Wilkes Booth assassinated President Abraham Lincoln. As the country reeled from four years of war and the death of 620,000 men—a full two percent of the country’s population—both armies began to send men home.

As a result, newspapers were filled with stories about the president and his assassin instead of the tale of how a group of obscure men, many of them former prisoners in some of the South’s most brutal prisons, perished in a terrifying explosion.

During the war, the steamer Sultana had been used to transport Union troops from St. Louis to New Orleans. That was its task in April 1865, too, but this time the ship was taking prisoners home.

The North and South were in the process of releasing hundreds of thousands of prisoners they had kept in captivity for the duration of the war—a conflict in which over 400,000 people were imprisoned. This number was unprecedented, and it created some real logistical and diplomatic problems for both sides. Though some prisoner exchanges took place during the war, the program broke down early on. Concerned that released prisoners would simply find their way back home and go back into battle, both sides simply kept them.

Thus, a gigantic number of prisoners needed to get home. Union soldiers suffered in prisons like Andersonville, where 13,000 or more died after suffering in overcrowded and squalid conditions. All of the men who boarded Sultana on April 24 had suffered through Andersonville and another camp, Cahaba, and had been awaiting release in a parole camp.

The United States turned to private citizens to get troops home, offering $5 per enlistee and $10 per officer to anyone willing to transport them North. To J. Cass Mason, who captained the steamer, this offer was irresistible. During the war, Mason had built a reputation as a riverman who could navigate a boat through tricky waters with impressive speed, even setting a speed record on his route. He had been the one to deliver news of the end of the war to Vicksburg in Sultana, a vessel that, despite needing a few minor boiler repairs on the way south, was known for being swift and reliable.

But Mason, who had sold most of the interest in Sultana to others, was in financial trouble. And he had some unsavory connections. In need of passengers, he spoke with Reuben Hatch, a Union lieutenant colonel who got in trouble for taking bribes and selling government supplies for his own profit during the war. Hatch told Mason about the Union’s offer—and told Mason he’d be happy to pack the boat as long as he got a kickback. Mason agreed.

Hatch delivered on this promise. With the help of a group of Union officers, he produced far more passengers than the ship was supposed to carry. The Union officers and Mason ignored warnings that there were too many passengers and crammed the now sagging boat with more and more men. And even when Mason complained that there were too many passengers, the officers loaded on more.

Despite being certified for 376 passengers and a crew, when Sultana embarked on the evening of April 24, it carried as many as 2,300 people—more than six times the boat’s limit.

Mason and his crew became increasingly worried as the journey continued. And their worries were well founded: After three days of sailing, Sultana’s leaky boilers exploded. As the ship burst into flames, screaming men did, too. Many of those who fell into the water immediately drowned because of their weak condition. Others were rescued by a nearby ship. Though the complete death toll is unclear, at least 1,100 people, and possibly many more, died that night.

So why was this unthinkable disaster so easily forgotten? Blame it on timing. National papers were mostly focused on presidential news and information about the execution of John Wilkes Booth, which occurred one day before the explosion. America was also inured to bloody battles as they had been inundated with large of casualties throughout the war. These victims were enlisted men, it couldn’t compete with other news of the day. News at that time also traveled more slowly, and few people heard about Sultana at all.

But Potter, who penned a book about the disaster and is still piecing together the personal stories of those involved, says that more than anything, Americans’ desire to move on from the Civil War buried Sultana’s story. “America at that time was so beaten down by the horrors of the American Civil War that it almost passed without a great deal of notice,” he says. “People were looking to the future.”

That desire for a better future buried the past—and raises questions about what other stories are lost when major news stories dominate newspapers and other forms of media. After all, the only way historians can go back in time is through the remnants of the past, and newspaper accounts are among history’s most precious witnesses.

Though they had suffered through prisons and a fiery, brutal death, the enlisted men who packed Sultana were no match for the flames of history. Perhaps if their deaths had been better covered at the time, they’d be as well known as the passengers on Titanic instead of a tragic historical footnote.