While the Scarlet Speedsters known as the Flash were the Fastest Men of their respective Earths, they were not alone in this regard. They had longtime partners in Kid Flash and Johnny Quick, and fleet female friends also aided the speedsters in Doralla Kan and Joanie Swift. However, today's pair truly set the tone for tenacity in their pursuit towards their goals.
Sgt Willie Walker was a Vietnam veteran whose combat wounds left him immobile. When he merged with an elemental force to become the Black Racer, Walker gained superhuman abilities including super speed and phasing attributes. Seeking out those residents of New Genesis and Apokolips who invaded his Earth-One, the Black Racer sought to eliminate their threat. In the future, the Racer used an alter ego as the Black Flash who sought out members of the Flash family.
Black Racer's counterpart was another mysterious man known only as Quicksilver. Having gained access to his own elemental speed force decades earlier, their "Laughing Robin Hood" used his super speed and vibratory techniques to carve out a heroic legacy for himself. Eventually, this loner joined forces with Uncle Sam and his Freedom Fighters in an undocumented adventure, leaving his native Earth-Two for the war torn parallel planet of Earth-X. However, it is speculated that he eventually returned to him home world when realizing the futility of saving his adopted home from Nazi forces. Eventually, in an alternate timeline, Quicksilver would meet the Flash and become a mentor of sorts.