Davros was a Kaled scientist who lived on the planet Skaro. He was crippled after an accident so he used a special designed weelchair for transport. He is responsible for the creation of the Daleks, although he was a genius he was also insane.
After almost dying in an accident on Skaro, Davros was left crippled and had to rely on a special life support system, which he could control like a weelchair. As the Kaleds and the Thals were at war with each other using chemical and nuclear weapons, Davros noticed that Kaleds infected by the radiation and chemicals began to mutate into strange mutant like creatures. Davros would conduct experimetns on these mutants and placed them in a special battle travelling machine, named the Mark III Travel Machine, which could help them survive. However Davros would remove all emotions and any form of pity from the mutant Kaleds, making them ruthless and emotionless monsters.
Though he created the Daleks, he couldn't control them and they soon killed him. However the Daleks would bring him back to life and revive him whenever they needed his knowledge, although he would be normally killed or inprisoned after he had served his purpose. This led Davros to create new Daleks that would obey him. These Daleks he named Imperial Daleks, and became their emperor. Amassing an army of millions, Davros set for Skaro, in order to take control of the entire Dalek race once and for all. Davros was unsuccessful, as the seventh incarnation of the renegade Time Lord known as the Doctor tricked him into using a stellar manipulator devices called the Hand of Omega to cause Skaro's sun to go supernova.
During the first year of the time war Davros was thought to be killed after his ship flew into the jaws of the Nightmare Child despite the Doctor's attempt to rescue him. When Dalek Cann used emergency temporal shift and went back to the Time War he rescued Davros and quickly made a new Dalek Empire within the Medusa Cascade. The New Dalek Empire was lead by a Red Supreme Dalek from within the Cucible. Here, Davros was kept as a 'pet' by the Daleks. In spite of this, the Supreme Dalek relied on Davros' knowledge and skill to obtain the capacity to destroy all of creation via the reality bomb. Davros, however, relied majorly on Dalek Caan's prophecies and when it turned out that Dalek Caan had not told Davros the complete truth, Davros was apalled. The Doctor, along with DoctorDonna and the Metacrisis Doctor, stopped Davros' plan before the reality bomb could be detonated. As the Doctor helped his companions escape the Cruscible Dalek Caan persuaded the Metacrisis Doctor to destroy all of the Daleks. The Doctor tried to stop him, but alas, the New Dalek Empire fell. Before the Cruscible exploded, the original Doctor tried to rescue Davros but Davros refused. Davros named the Doctor the 'Destroyer of the Worlds' just before his surroundings went up iin flames. It is unknown whether he surrvived but, knowning Davros, it is likely he remained alive.