Manfred Mota, nuclear engineer turned small-time bank robber turned psychotic, had fought each of the three 20th-Century Flashes. His battle with Wally West led to his becoming a creature of living plutonium with a monomaniacal obsession on the Flash, smoldering away underneath Central City. He resurfaced in the year 2645, threatening the city, and so tachyon physicist John Fox was sent back in time to recruit the aid of the Flashes who had defeated Mota before. He failed to make contact, but his unstable return trip through time imbued him with super-speed. He donned a combination of several costumes from the Flash Museum and the name of Flash, and defeated Mota on his own (Flash 50th Anniversary Special, 1998).
Fox began a career of his own, but advances in technology soon produced “Speed Metal”—super-fast machines that patrolled the streets, leaving him to guard the Time Institute. Fox resented the lost chance to be a hero.
An encounter with Wally West (Flash #115, 1996) led him to realize that Wally probably would not be present to deal with a great catastrophe in the late 20th century, so Fox decided to take a trip through time and take his place—as completely as possible. Linda, believing Wally dead, turned to John, Wally lost his beacon... and Fox proved incapable of handling the disaster when it struck. Wally returned, nonetheless, stopped the disaster, and helped Fox evade Speed Metal when they came after him for violating strict laws against time travel—laws with no statute of limitations.
A fugitive in his own time, Fox began searching the timestream for a place he could belong. Along the way, he helped a 30th-century couple send their infant daughter Iris to safety in the 20th century (Flash 80-Page Giant #1, 1998). Ultimately, he found himself in the year 85,265, an era in which time travel was no longer forbidden, and joined the ranks of Justice Legion A (DC One Million #1, 1998).
Shortly before the One Million Crisis, Fox’s time gauntlets were stolen by Chronos to ensure he would not interfere with the carefully-laid plans (Chronos #1,000,000, 1998). Whether Chronos actually returned them is unclear, but Fox appears to have since built the time-travel technology directly into his suit.