The Kaleds (an anagram of Daleks), also known as Dals, are a fictional race of humanoid extraterrestrials from the British science fiction television series Doctor Who and the forebears of the Daleks.
In the first Dalek serial, commonly known as The Daleks (1963), Thal history recorded that the planet Skaro was once home to two humanoid races: the peaceful and scientifically-advanced Dals (who were described as philosophers and teachers) and the warlike Thals. Following a short but terrible nuclear war between the races, the Dals were mutated and became the aggressive and xenophobic Daleks.
This information was contradicted in the 1975 serial Genesis of the Daleks, in which the Doctor returned to Skaro before the creation of the Daleks. In the later serial, it was the Kaleds who waged war on the Thals, and the conflict was a generations-long war of attrition, not the short nuclear exchange previously described. The Kaleds, with their grey-black uniforms, stylized salutes and authoritarian political structure, were thinly veiled analogues of the Nazis. The serial also suggested that mutations among the general Kaled populace were not as advanced as implied by the earlier account, and that the development of the mutated creatures that became the Daleks was engineered by the Kaled chief scientist Davros — head of the Kaled Science Elite — for his own purposes (but it is suggested that he was only speeding up the process, in order to predict the final form of the Kaled mutation, and seeing its helplessness, devised the means for his race's continued existence, but of course using his own creations to prematurely replace the non-mutated members of his race with the Daleks).
All later serials followed the Genesis version of the story and treated the "Kaleds" as the predecessors of the Daleks.
Several theories exist to explain the discrepancies caused by the Genesis production team's rewrite of Skaro's history. One theory holds that the account in The Daleks, which comes from centuries-old Thal oral history, is simply wrong (in the Big Finish Productions I, Davros audio dramas, the Dals are a long-extinct nation by Davros's time). Other more complicated theories, making use of the time travel aspect of the series, have also been suggested.
The mutant beings inside Dalek casings are sometimes referred to as "Kaleds" or "Kaled mutants" to distinguish them from the cyborg Daleks. In particular, the casings, Mark III Travel Machines, should not be called Daleks. However, casing-free Daleks can still properly be called Daleks as well.