John L. Thunder was born on 7 July 1917, a Saturday - the seventh day of the seventh month in a year ending in a 7 and on the 7th day of the week. This coincided with the 7th Circle of the Mooon Lahseen in the the calendar of the small Asian country of Badhnisia. The high priest of that country sent agents to kidnap the child, and in a ceremony which involved a belt bearing the Eternal Zone of the Zodiac being place around the child, the enchanted words Cei-U (Say You) were spoken 7 times.

Thus a spell was cast upon the boy that would be activated on his 7th birthday. Because enemies of Badhnisia discoverd the powers the child would have, they tried to capture him, but he was returned - with the aid of a birthmark - to his rightful parents in the US. Johnny was unaware of the powers he had until he was 22. He was at the first meeting of the JSA and became their mascot - until the Flash (Jay Garrick) resigned his membership and Johnny was chosen to replace him. During WW 2, Johnny joined the US Navy.

When that conflict ended, Johnny was 28 (4x7) - a power high. After that year, the high priest cast a spell which led to a gradual reduction in Johnny's powers, so that the Thunderbolt only responded to about 1 in 4 calls. Eventually Johnny's power disappeared completely, and he had to resign from the JSA - his place being taken by Black Canary, whom he had a crush on.