Born in Clay County, Missouri in 1847, Jesse James grew up as part of a Confederacy-supporting, slave-owning family. As a teen in 1864, James and his brother Frank joined a guerrilla unit responsible for murdering dozens of Union soldiers.

For some historians, James never stopped fighting the Civil War, translating his fury over the defeat of the secessionist cause into a career sticking up banks, trains and stagecoaches. At times, he saw himself as a modern Robin Hood, robbing from the politically progressive Reconstruction supporters and giving to the poor.

According to the State Historical Society of Missouri, the James-Younger gang operated widely, from Iowa to Texas to West Virginia. Overall, between 1860 and 1882, they are believed to have committed more than 20 bank and train robberies, with a combined haul estimated at around $200,000. While they usually focused more on robbing train safes than individual passengers, they did ruthlessly murder countless people who got in their way.

As newspapers began to mention James, his love for the attention grew.

"He was audacious, planning and robbing banks in the middle of the day and stopping the most powerful machines of the time—railroad engines—to rob their trains and successfully get away,” wrote Bill Markley in Billy the Kid and Jesse James: Outlaws of the Legendary West.

The James legend grew with the help of newspaper editor John Newman Edwards, a Confederate sympathizer who perpetuated James's Robin Hood mythology. "We are not thieves, we are bold robbers,” James wrote in a letter Edwards published. "I am proud of the name, for Alexander the Great was a bold robber, and Julius Caesar, and Napoleon Bonaparte."

But while he did steal from the rich, there's no evidence James gave to the poor.

In 1881, the governor of Missouri issued a $10,000 reward for the capture of Jesse and Frank James. On April 3, 1882, at the age of 34, James was shot and killed by one of his accomplices, Robert Ford, who was found guilty of murder but pardoned by the governor.

Legend says the Wild West outlaw Billy the Kid—cattle rustler, gunslinger, murderer, escape artist—killed 21 people before he turned 21 years old, his age at death. The reality may be closer to nine. But the early days of Henry McCarty, later known as William Bonney, "the Kid," are murky.

Billy the Kid was likely born in New York City in 1859, later moving to Indiana, Kansas and Denver before his family settled in Santa Fe, New Mexico. Orphaned as a teen after his mother died of tuberculosis, Henry was separated from his brother and placed in foster homes. It wasn’t long before he fell into petty theft. After a September 1875 arrest for stealing clothing from a Chinese laundry, Henry reportedly shimmied up the jailhouse chimney and escaped, ultimately making his way to southeast Arizona.

In 1876, he took up with an Arizona gang known for stealing horses. In 1877, after being charged with murdering a blacksmith, he fled home to New Mexico and joined another band of thieves. In 1878, he joined a posse called the Regulators set on revenge for a cattleman's murder in what came to be called the Lincoln County War. By 1880, his name was spread across tabloid newspapers.

“Billy became the symbol of the American loner: the little guy fighting against all odds; the misunderstood youth who battled the combined corrupt government and business forces hell-bent on his destruction,” wrote Markley. “Everyone wanted to be associated with Billy the Kid—he stayed at their ranch or he stole one of their horses.”

With a $500 reward on his head, the fugitive was gunned down by New Mexico Sheriff Pat Garrett on July 14, 1881.

Born to a well-to-do, Confederate-sympathizing family, Myra Maybelle Shirley Starr—later known as Belle, and, eventually, the "Bandit Queen"—was a teenager in Scyene, Texas, in 1864 when outlaws Jesse James and the Younger brothers used her family’s home as a hideout.

In the years that followed, Starr married three outlaws: Jim Reed in 1866, who ran with the Younger, James and Starr gangs and was killed in 1874 by police; Bruce Younger In 1878; and Sam Starr, a Cherokee, in 1880.

After Belle and Sam Starr were later charged with horse stealing, a federal offense for which she served time, she was again charged with horse theft in 1886. This time, because of her legal skills, she was acquitted. But in the meantime, her husband and an Indian policeman had shot each other to death.

Starr herself was murdered February 3, 1889, at the age of 40, close to her Oklahoma cabin in the Cherokee Nation. Some suspect her son, Ed Reed, whom the Texas State Historical Association asserts she had recently beaten for mistreating her horse. The crime has never been solved.

Two days following her death, The New York Times called her “the most desperate woman that ever figured on the borders.”

But according to Glenn Shirley, author of Belle Starr and Her Times: The Literature, the Facts, and the Legends, the only truth in the report was the fact that she had died.

“Almost overnight, the name of Belle Starr became a household word throughout the nation,” he writes. “She had been elevated to a seat of immortal glory as a sex-crazed hellion with the morals of an alley cat, a harborer and consort of horse and cattle thieves, a petty blackmailer who dabbled in every crime from murder to the dark sin of incest, a female Robin Hood who robbed the rich to feed the poor, an exhibitionist and clever she-devil on horseback and leader of the most bloodthirsty band of cutthroats in the American West. All this despite the lack of a contemporary account or court record to show that she ever held up a train, bank or stagecoach or killed anybody."

Born Robert LeRoy Parker in 1866, in Circleville, Utah to devout Mormons, the famed outlaw who later adopted the moniker Butch Cassidy grew up dirt poor, one of 13 children. As a teen, working on a nearby ranch to help feed his family, legend has it he met Mike Cassidy, a cattle rustler and mentor, who taught him, according to Time, "how to make a better, if distinctly dishonest, living."

Landing in the gold rush town of Telluride, Colorado, Cassidy, along with three other men, on June 24, 1889 committed the first crime attributed to him—a bank robbery, during which the trio made off with $20,000.

Adopting his new name (some say "Butch" comes from time spent working as a butcher) and hiding out in Wyoming, he began adding outlaw cowboys to his gang, known in the press as the "Wild Bunch." They included Harry Longabaugh, aka the Sundance Kid.

After spending 18 months in prison for horse theft in 1894, in 1896, Cassidy’s Wild Bunch robbed a Montpelier, Idaho bank, stealing $7,000. The gang went on to commit several other robberies in the Southwest, including a $70,000 haul during a Rio Grande train robbery in New Mexico.

With the authorities hot on their trail, Cassidy and Longabaugh eventually fled to Argentina. Eventually, Cassidy went back to robbing trains and payrolls up until his alleged death in 1908.

Now, about that death: Most historians say Butch and Sundance, immortalized in the Robert Redford/Paul Newman movie, died in a shootout in Bolivia, but others theorize the pair escaped, living out their lives under aliases.

Did he kill 20 men? Forty? Fifty? The total body count may be unclear, but according to John Wesley Hardin, they all deserved it. "I never killed anyone who didn't need killing," he famously said.

By all accounts, Hardin was one of the most dangerous gunslingers in the American Southwest. “When compared with John Wesley Hardin, Billy the Kid was a rank amateur,” wrote Lee Floren in his book John Wesley Hardin: Texas Gunfighter. “For by the time Wes Hardin reached his 21st birthday, he was credited with killing 27.”

Born in 1853 in Bonham, Texas to a Methodist preacher, Hardin displayed his outlaw nature early: He stabbed a classmate as a schoolboy, killed a Black man during an argument at 15 and, as a supporter of the Confederacy, claimed to take the lives of multiple Union soldiers soon after, according to the Texas State Historical Society.

More than a dozen killings later, he surrendered in 1872, broke out of jail, joined the anti-Reconstruction movement and just kept killing, the society reports. Fleeing capture with his wife and children, he was nabbed by Texas Rangers in Florida in 1877 and sentenced to 25 years for the murder of Charles Webb, a deputy sheriff. During his prison term he tried repeatedly to escape, read theological books, served as superintendent of the prison Sunday school and studied law, according to the society. He also wrote his autobiography. Hardin was pardoned on March 16, 1894, and subsequently admitted to the bar.

But life on the straight and narrow didn’t last long. According to the society, Hardin hired assassins to murder one of his clients—with whose wife he was having an affair. And on August 19, 1895, Constable John Selman, one of the hired guns, shot and killed Hardin in the Acme Saloon—ironically, it is believed, because he had not been paid for the hit job.