Beginnings
While there are several theories about the game's origin, no one seems to know with certainty exactly how and where it began. The most logical theory presented on the FindSportsNow website suggests that it was developed by a gym teacher looking for a new indoor activity for his students. The earliest known rules are directed toward youngsters and appear to be set for a short time period like recess.
Early Rules
The earliest rules called for players to be divided into two teams, with one team forming a circle and the other standing inside it. Players on the outside threw a ball at someone in the circle. If any person inside the circle was hit, he joined the outside team. Play continued until only one person was left.
Variations
Another early version called for the hit players to leave the circle and wait on the outside until all team members are out. The two teams then changed places. Still another form played with a small number of people required all but one player to line up opposite a wall or side of a building. Those in the line tried to hit the person moving in front of the wall. Whoever hit the person took his place the one that got hit joined the line.
Competition Rules of Play
The basic concept of throwing a ball at someone who tried to avoid it remained the same even as dodgeball took on standardized rules. It's not clear what kind of ball was used in the early games, but eventually a "safe" ball that would not cause injuries was put in play. Organized leagues use a ball weighing 7 oz. and measuring 8 inches in diameter. The ball is cloth covered to keep it from stinging on impact.
The match play rules evolved to cover where players start a match, how balls are obtained at the start and the second-life format where hit players can return to a game if a teammate catches an opponent's throw. This is the format featured in the "Dodgeball" movie.
Popularity
As of 2010 almost all states have active dodge ball organizations and the International Dodge Ball Federation has almost 300,000 players.