The Daleks were a warrior race made up of genetically-engineered mutants.
By most accounts, they were the faction that opposed the Time Lords in the Last Great Time War. According to one account, the Eighth Doctor eventually turned to the Moment to destroy both the Daleks and the Time Lords in order to end the War. The Time Lord's homeworld of Gallifrey was destroyed as was most of both races. The Doctor survived in a new incarnation (PROSE: Doctor Who and the Time War) as did several groups of Daleks. (TV: Dalek, Bad Wolf et al.)