The Flash's History
Jason "Jay" Garrick is a speedster and founding member of the Justice Society of America. As a result of Doctor Manhattan's alterations to the timeline, Jay became trapped in the Speed Force and forgotten to all. After Manhattan had undone his edits to reality, Jay and the rest of JSA had been rewritten into the timeline so that they had always existed.
During the year 1940, Jay operated as the Flash in Keystone City. As a result of the altered timeline, Wonder Woman became the world's first superhero and inspired Garrick, who was amidst an existential crisis, to do more to help people by fighting the Nazis in Europe. While facing Thinker, he heard a mysterious voice that warned everyone will forget him. After defeating Thinker, he realized that he was meant to become part of something bigger.
Jay became a member of the Justice Society of America alongside Hawkman, Hawkwoman, Green Lantern, Wildcat and The Sandman.
Jay was enlisted by President Roosevelt for a secret mission to retrieve the Spear of Destiny from the Philippines before the Nazis could obtain it. He was partnered with Happy Terrill, aka the Ray, who unlike other early superheroes was a government agent who maintained a low profile and was largely unknown. Jay was awed at the prospect of finding the spear that pierced the side of Christ, although the atheist Terrill was only concerned with the Spear's strategic value. They were beaten to the Spear by a band of Nazis lead by Parsifal and captured, as Parsifal possessed the ability to negate their superpowers. The two were held prisoner and tortured for five weeks on a German warship, and although Jay was initially defiant he eventually lost hope, asking Terrill to carry a message back to his girlfriend Joan if he didn't make it.
The Ray prayed for a miracle, which was answered when lightning exploded from Jay's chest, breaking their chains and blasting the cell door open. Unbeknowst to the Ray, Jay had been possessed by the consciousness of Wally West, a successor of Jay from the 21st Century and the lightning was excess Speed Force energy. Looking out of the porthole, they realised that the ship had landed and Parsifal had handed the Spear over to Hitler, who had also been granted powers by the lightning. Wally and the Ray escaped the ship disguised as German soldiers and chased after the plane Hitler and Parsifal were leaving on. In the future, Barry Allen advised Wally to drain the Speed Force energy within Hitler into the Spear.
The two made it aboard the plane and Hitler used the power of the Spear to take control of their minds. However, when he froze Wally's mind it allowed Jay to take control back of his body. Unsure of where he was or what was happening, he ran forwards and punched Hitler in the face, breaking his command over the Ray. The Ray grabbed the Spear from Hitler and drained the excess Speed Force energy into it. The explosion of energy destroyed the plane but the Ray flew away to safety carrying Jay. Wally was back in control and asked the Ray to get Jay to a hospital before he was pulled back into the timestream. Jay awoke to find Terrill carrying him in midair and panicked, having no idea how he got there. He would retain some memories of their adventure but could not recall details besides punching Hitler in the face.
Battling the Legion of Doom
Jay and the rest of the Society encounter John Stewart and Barry Allen. Jay expresses surprise about their being another Flash. He, the other society, John and Barry go to Pearl Harbor, shortly before is attacked by the Japanese. He and his allies battle the Legion of Doom and the Japanese forces under their control, before Aquaman shows up.
The Button
When Barry Allen and Batman raced through the Timestream after Eobard Thawne, Jay attempted to call out to Barry from inside the Speed Force. After finally getting Barry's attention, Jay was able to break through and use his speed to get Barry, Bruce, and himself out of the timestream and back on Earth.[1]
After getting back on Earth, Jay began slowly fading back into the Speed Force. He introduced himself to Barry, who had no idea who he was, trying to get him to remember him, as he did with Wally West. Jay told Barry that someone took everything from him and he didn't know why. Just before fully fading back into the Speed Force, Barry grabbed Jay's arm and attempted to save him from fading away, although just as he grabbed him, Jay was teleported away by a blinding blue light.
Doomsday Clock
It was revealed that the Justice Society of America had been erased from history due to Dr. Manhattan causing Alan Scott's death. Since Scott was the major lynchpin behind creating the JSA, his death meant the group never existed in the first place.
Dr. Manhattan however undid his actions after getting inspired by Superman, causing Scott to survive and becoming a superhero, restoring the JSA along with Garrick back into the timeline. The team came to assist Superman in stopping the metahuman battle in Washington, D.C.
Manhattan's attempt at fixing the timeline and reality failed however, as they merely re-adjusted into a new version. Jay returned to the present timeline along with other Justice Society members when Wally West, having gained the powers of Dr. Manhattan and acquiring the Mobius Chair, attempted to fix time by merging the various timelines, but he was now significantly old.
Reunion
Jay was restored to the timeline but had lost his memories, which he later recovered. He had also married Joan and though they didn't have kids of their own, they treated Barry and Wally as their own sons.
Wanting to talk to Barry after recovering his memories, he tracked him down using the Speed Force, but found him threatening Iris West, Avery Ho, Wallace R. West and Bart Allen. He knew the man couldn't be Barry and found that Eobard Thawne had taken control of his body, while engaging in a brawl with him and telling the others to stay back. Just at the moment when Thawne outmatched his opponent, he was struck with great pain due to Barry trying to take back control of his body. The reunited Flash Family then arrived at Central City's graveyard to stop Thawne and his Legion of Zoom recruited from various points of timelines, from taking Nora Allen's body, after getting a tip from the Trickster, James Jesse.
The Tornado Twins soon attacked them but returned to their time after regaining their memories. As Thawne directed the remaining members of his legion to attack, Barry started taking control of his body back. Gorilla Grodd encouraged the other members to kill him, which would allow them to kill both Thawne and Barry, but they were stopped by Jay and the Flash family. As Barry, took back control and brought Jesse Quick as well as Max Mercury out of the Speed Force, Thawne revealed that he had far more Flash Villains across the timeline for his Legion of Zoom than they knew.
As Jay and others struggled to battle the Legion of Zoom, Max Mercury meditated and brought forth speedsters from various realities to help them. As Thawne escaped after getting struck by a lightning and hearing Wally, the kids made a plan to send the Legion of Zoom back to their time by creating a shockwave frequency to do so. Jay, though reluctant, was persuaded by Max to let them do what they wanted. covered them along with the other older speedsters. The Flash finally ended the threat of Thawne by grounding him and giving him part of his speed force, which removed his state of being a paradox that could avoid changes in the timeline.
Death Metal
The world was soon transformed to a nightmarish landscape when the Batman Who Laughs conquered Earth 0 with the help of Dark Knights and was granted power by Perpetua to rule over it as he saw fit by Perpetua, in return for helping her. Jay and the other surviving JSA members guarded the Valhalla Cemetery where deceased JSA members were buried. Barry knew where they were and kept in contact. When Wonder Woman came looking for Batman, whom they had allowed in to recruit his undead army, he also reunited with Wally.
When the Robin King later came to cemetery, they realized the Batman Who Laughs had become immensely powerful and he along with Wally as well as Barry ran through a portal created by Doctor Fate. The Batman Who Laughs, who had now gained Doctor Manhattan's powers, chased them and nearly caught up to them since the Speed Force had grown weak. The three speedsters then combined their powers to outrun him.
During the final stand against the Darkest Knight's army, Jay faced various villains, including a Nazi version of himself from the Last 52 Multiverse.
Later that day, along with Barry, Jay fought against a Last 52 version of Wally West, who still possessed Doctor Manhattan's powers, and was killed by its blue lightnings. However, after the Hands restored Earth 0 to its Pre-Metalverse state, Jay was resurrected along with the other people killed during the invasion.
