Billy the Kid - Wikipedia

He lists two possible dates. Billy the Kid (born Henry McCarty, also known as William H. Bonney; 1859 – July 14, 1881) was an American Old West gunfighter who participated in the New Mexico Territory's Lincoln County War of 1878. He is known to have killed eight men.[2][3]
His first arrest was for stealing food in late 1875, and within five months he was arrested for stealing clothing and firearms. Two days later, Bonney escaped from jail and fled from New Mexico Territory into the neighboring Arizona Territory, making him both an outlaw and a federal fugitive. After murdering a blacksmith during an altercation in August 1877, Bonney became a wanted man in Arizona Territory and returned to New Mexico, where he joined a group of cattle rustlers. He became a well-known figure in the region when he joined the Regulators and took part in the Lincoln County War. In April 1878, the Regulators killed three men, including Lincoln County Sheriff William J. Brady and one of his deputies. Bonney and two other Regulators were later charged with killing all three men.
Bonney's notoriety grew in December 1880 when the Las Vegas Gazette in Las Vegas, New Mexico, and the New York Sun carried stories about his crimes.[4]Sheriff Pat Garrett captured Bonney later that month. In April 1881, Bonney was tried and convicted of the murder of Brady, and was sentenced to hang in May of that year. He escaped from jail on April 28, 1881, killing two sheriff's deputies in the process and evading capture for more than two months. Garrett shot and killed Bonney—aged 21—in Fort Sumner on July 14, 1881. During the following decades, legends that Bonney had survived that night grew, and a number of men claimed to be him.[5]