The first steamship was built in France in the late 1700s but it was in the new United States that they came widely into use. The first commercially successful steamboat was Robert Fulton's Clermont which began operating in 1807 between New York City and New Jersey and the first steamboats appeared on the Mississippi and Ohio Rivers in 1811 and 1812.
Paddle steamers have a romantic image (think of the musical Show Boat) and remained in common use on the Mississippi well into the early 20th century. But they also were inherently prone to risk of catastrophic failure.
The steamers were powered by large boilers (usually four and consuming 5 to 15 tons of coal a day) located between the paddles to generate steam and turn the wheels. Operating at high pressure in an environment where pressure gauging was rudimentary and construction techniques and quality highly variable, safety often depended upon the constant supervision of the boilers by a competent engineer. Disasters were not uncommon and there are many instances when boilers failed resulting in explosions, fire and scalding steam being sprayed over passengers and crew.
Samuel Clemens, later better known as Mark Twain, was a steersman on the Mississippi River steamer Pennsylvania. A few days after he left the boat in 1858 it exploded killing most of those aboard, including Twain's brother. The Pennsylvania disaster resulted in a couple of hundred deaths like most of these incidents. The huge scale of the Sultana disaster in 1865 was a byproduct of the conditions surrounding the end of the Civil War.
As the Confederacy collapsed in April 1865, thousands of Union prisoners were released from camps operated by the rebels and the Federal army was seeking ways to get them home quickly, along with other sick and hospitalized soldiers. Many of them, including some from the notorious Andersonville prison in Georgia, were transported to the area around Vicksburg, Mississippi.
The Sultana was built in Cincinnati going into service in 1863. In April it started a trip downriver making multiple stops, including at Vicksburg, before reaching New Orleans, where it loaded about 150 civilian passengers for the trip back upriver starting on April 21.
The Vicksburg stop on the downriver route was crucial. Captain J Cass Mason met with Army officers responsible for arranging for the return of soldiers in order to arrange to pick up a load on his return trip upriver. It was a lucrative contract for any steamboat owner, paying $5 a head per enlisted man and $10 for officers.
As Sultana neared Vicksburg on its return trip steam began escaping from a crack in one of the boilers and the boat limped into the city. After looking at the boilers a local boilermaker told the captain that extensive repairs were required. Under pressure to get underway quickly so he could board the soldiers before they could get on another steamboat the captain pressured the boilermaker to do some quick patches, promising he would make full repairs when Sultana reached St Louis.
During the 24th, the former prisoners boarded the vessel. The rated carrying capacity of Sultana was 376, which since the crew was 80-85, meant about 290 passengers but on that day about 2,100 soldiers were allowed to board by the military authorities and the captain bringing the total onboard to around 2,300.
(Sultana at Helena, Arkansas the day before explosion from Wikimedia)
Sultana slowly made its way north on the river. The soldiers, jammed together, slept on the open deck. The crew had to work to control the passengers because any sudden movement in one direction could capsize the overloaded boat. Then, without warning, at about 2AM on April 27, the boilers exploded. Many of the passengers and crew were immediately killed and the rest thrown into the water or clinging to the remains of the boat as it sank. There were only two small lifeboats and many of the soldiers who were ill and/or weakened from their captivity had little strength left to save themselves.
(The Sultana on fire from Harper's Weekly)
HistoryNet carried a vivid description of the horror of that night:
Suddenly, three of the huge boilers exploded with a volcanic fury that a witness on the shore described as the thundering noise of 'a hundred earthquakes.' The blast tore instantly through the decks directly above the boilers, flinging live coals and splintered timber into the night sky like fireworks. Scalding water and clouds of steam covered the prisoners who lay sleeping near the boilers. Hundreds were killed in the first moments of the tragedy. The upper decks of the Sultana, already sagging under the weight of her passengers, collapsed when the blast ripped through the steamer's superstructure. Many unfortunate souls, trapped in the resulting wreckage, could only wait for certain death as fire quickly spread throughout the hull. Within twenty minutes of the explosion, the entire superstructure of the Sultana was in flames.You can also read a New York Times account of the event from April 29, 1865.
The burning wreckage began to drift slowly downriver, as those on board fought to survive. With only 76 life preservers and two small lifeboats available, most of those who survived the blast jumped for their lives into the river. In the hours before dawn, hundreds of soldiers and civilians struggled in the river as they awaited rescue. But help did not come until 3:00 a.m., an hour after the explosion. The Bostonia II, plowing downriver, came upon the Sultana engulfed in flames, and immediately began to haul the survivors from the water around the wreckage.
Although several hundred were rescued, many were horribly burned and at least two hundred died in the next few days. The death toll remains unknown but is estimated to be 1,700-1,800. So many who had suffered yet survived the war dying so close to getting home.
An Army investigation concluded that its officers were negligent in allowing the overloading of the vessel but court-martial proceedings did not result in any convictions despite the clear evidence of negligence and incompetence (along with some indirect evidence of bribery).
The remains of the Sultana were discovered in 1982 in a filled-in former channel of the Mississippi River.