Very little is known about the Joker's history prior to choosing a life of crime, other than he was a poor man. His original birth name was never clarified, though some accounts depict it as Joe Kerr though many assume this was an alias and not his actual birth name.

Finding honest work unfulfilling of his personal ambitions, he turned to crime to amass a personal fortune for himself. He first gained attention in early 1940 when he was operating as a masked professional criminal leader known as the Red Hood. The Red Hood and his men attempted to rob a profitable manufacturing business adjacent to a chemical processing plant. Batman and Robin arrived on the scene and the Red Hood abandoned his henchmen, seeking to escape by running through the chemical plant. Batman and Robin cornered him on a catwalk and the Red Hood was left with little choice but to dive off the catwalk into a large vat of steaming chemicals. According to Gotham City files, the chemicals were the inks used to make playing cards. The chemical factory was listed as the "Monarch Card company", which would prove to be prophetic in the criminal's own development. Batman and Robin naturally assumed that their adversary died being exposed to the heated toxic chemicals. The Red Hood actually survived the chemical bath and managed to escape through a drainage pipe that emptied out into the river. However when he emerged from the waste pipes, he discovered that the chemicals turned his hair green, his skin chalk-white and his lips rouge red. Driven partially insane from the experience, the criminal decided to pattern himself after the playing cards Joker character that the chemicals were used to create.

Life after the incidentEdit

Soon after his recreation and new name, the Joker quickly became a noted criminal entity in Gotham City's criminal underground. He did this when he brazenly challenged Gotham's underworld and police department by announcing over the radio that he will kill three of Gotham's most prominent citizens: Henry Claridge, Judge Drake and Jay Wilde. Batman and Robin investigated the crimes and were startled to find the victims' bodies stricken with a macabre perpetual grin upon their faces. The Joker managed to trap Robin and was prepared to murder him with the same deadly Joker venom that he used on his other victims, but Batman rescued Robin and the Joker went to prison.

The Joker did not stay in prison very long however. He soon escaped via an explosive capsule concealed in a molar, and continued his never-ending crime spree. The Batman laid a trap for the Joker, baiting him to steal a valuable ruby gemstone. The plan worked and the Joker crossed swords with Batman and Robin once again. During their fight, the Joker was accidentally stabbed by his own knife and nearly died. He was taken to the hospital, but quickly recovered. A criminal cartel known as Crime Syndicate, Inc. took him from the hospital and offered them the position of leader of their gang. The Joker led Crime Syndicate, Inc. on a string of jewel robberies, but the organization collapsed after another encounter with the Batman. The Joker was left for dead inside of a burning building, but again, managed to survive.

The Joker's resilience and uncanny knack for cheating death came into play once again. While using a music store as a front for his criminal ventures, taking on the alias of A. Rekoj, he would hire thugs to steal for him. Ultimately, he'd reveal himself as the Joker and steal the loot from the thugs, who were completely flummoxed because they did not realize that A. Rekoj and the Joker were one in the same. During this caper the Joker once more ran afoul of Batman and Robin. Next the Joker stole a valuable item known as the Jade Buddha and fought the Dynamic Duo once again aboard a ship. The Joker was defeated and fell from the deck of the ship into the water, where he seemingly drowned.

He soon returned however and started up a new gang based on circus performers. It was at this time that the Joker's compulsion towards foiling the Batman intensified, and he deliberately began leaving riddles and obscure clues at his crime scenes, daring the Batman to solve them. He would also escape this caper, seemingly drowning when he tries to escape through a sewer tunnel, however he would survive this encounter as well. Joker's next plot would involve setting up an illegal gambling ship three miles into international waters with the aid of three other criminals: Queenie, Diamond Jack Deegan and Clubsy. Investigating the ship as Bruce Wayne, the Batman would learn of the Joker's involvement of the operation and end it's exploitation of it's clientele. The Joker would once more escape capture by jumping into the icy water below the ship, miraculously the clown prince of crime would cheat death once more. His current where abouts are unknown.