NEW YORK — Although its 147th anniversary is this month, the worst shipwreck in U.S. history is seldom talked about, as films, headlines and lavish re-creations surround the Titanic.

The S.S. Sultana, a steamboat carrying soldiers newly released from Confederate war camps to their homes in Ohio and Tennessee, sank abruptly in the Mississippi River on a dark night near Memphis after a boiler exploded and sent the men flying into the chilly water. It was April 27, 1865. The wreck killed roughly 1,800 people.

“It’s one of the most incredible historic stories in America that nobody knows about,” said Jerry Potter, author of the book “The Sultana Tragedy: America’s Greatest Maritime Disaster,” which was published in 1992.

“These prisoners of war were headed home and just a few days from finally seeing their families again,” said Norman Shaw, founder of the Association of Sultana Descendants and Friends. “That’s the heartbreak of this story.”

Although the Mississippi River disaster killed about 300 more people than Titanic’s 1,514 casualties, the Sultana and its victims have been virtually forgotten.

“I’m still amazed that so few people know about it,” Potter said. “I mean, there’s never been a movie about the Sultana. And the story to me is more compelling than that of the Titanic.”

The steamer, known to have a defective boiler, was severely overpacked. Its legal capacity was 376, but was carrying more than seven times that many passengers when disaster struck.

Even at the time, the wreck got relatively little attention.

John Wilkes Booth had shot President Abraham Lincoln two weeks earlier, and Lincoln’s funeral train procession was still making its way around the North.

The day before the Sultana wreck, Union cavalry men had tracked Booth to a Virginia barn and killed him. Earlier that month, Confederate Gen. Robert E. Lee had surrendered. Coming off a now unfathomable period when 600,000 people were killed by fellow countrymen, the public, Shaw and Potter said, was callous about death.

The only official gathering to commemorate the Sultana anniversary this month is expected to draw between 60 and 70 people to Cincinnati, where workers built the ill-fated ship in 1863.

Shaw created the descendants’ group in 1987 to revive and spread the Sultana story, though he didn’t have an ancestor on board. Planning for the 2015 sesquicentennial is under way, he said, and it includes the possibility of opening a museum dedicated to the Sultana wreck in Marion, Ark., the last port where the steamer stopped.

Carly Worth of Camarillo, Calif., had never heard of the Sultana wreck until a few years ago when a relative sent an obituary of her ancestor, Jonathon Bashir. According to the 1877 newspaper account, Bashir, a Union soldier who had been held at Andersonville, a prison camp in Georgia, was “on board the unfortunate steamer which was burned on the Mississippi River.” Worth remembers her husband, Don, a Civil War buff, saying, “You’re kidding me! He was on the Sultana.”

Aside from those with a keen interest in the Civil War or in maritime disasters, it’s tough to find people who have heard of the unfortunate steamer.

Sitting on a Manhattan, N.Y., bench looking out at a shimmering Hudson River near the 12th Street pier at which the Titanic should have docked in 1912, Ruth Kassanga guessed that the ocean liner’s encounter with an iceberg prompted the worst shipwreck of all time.

“I’m surprised I’ve never heard” of Sultana, she said.

Nor did the name Sultana ring a bell for Luisi Amado, also lounging near the pier. “Why is it we don’t recall that one?” she questioned.

Of 10 people near the dock asked what the worst U.S. shipwreck of all time was, all either answered Titanic or said they didn’t know. Not one answered Sultana. And even if they had, they still would have been wrong.

There have actually been five shipwrecks worse in human toll than Titanic.

A Soviet submarine in the Baltic Sea torpedoed the Wilhelm Gustloff, a ship overcrowded with German refugees toward the end of World War II, killing an estimated 9,200 people.

Then there’s the Dona Paz, which sank after colliding with an oil tanker in 1987 off the coast of the Philippines, taking around 4,000 lives, more than double the Titanic.

Another ship collision killed about 2,000 Canadians and injured another 9,000 in Nova Scotia in 1917, after a warship packed with explosives hit a passenger ship just offshore, near the crowded harbor city of Halifax.

And less than a decade ago, in 2002, a Senegalese ferry carrying about 2,000 people capsized in five minutes, killing all but a couple of dozen on board.

Perhaps our fascination with Titanic, even though it’s far from being the worst wreck, has to do with a past and present societal obsession with celebrity. Titanic carried some of the day’s most known and most affluent figures.

“History,” Potter said, “tends to remember the rich and the famous and forget the common people.”