The Original Purpose of Fallout's Vaults Revealed.

Tim Cain, one of the original creators of the Fallout series, has revealed that the vaults in the game were initially meant to send people to space to find a new planet to live on. The Enclave and the U.S. government saw the nuclear war coming and decided to take their "best and brightest" to space. However, they realized that this couldn't be done before the bombs dropped, and Vault-Tec thought it could use their vaults as trial runs to help get them to space. The vaults were never meant to release people back so they could repopulate the earth.