2150s Dalek invasion of Earth

In the second half of the 22nd century, the Daleks invaded Earth and occupied it for about ten years.

Prelude
The first incident of the invasion came in 2157, when Earth was bombarded with meteorites. At first this was thought the result of a cosmic storm, but shortly after things had returned to normal, people started dying of a new plague sent by the Daleks via the meteorites. The majority of the population of Africa, Asia and South America died before humans could find a cure. (DW: The Dalek Invasion of Earth)

Some humans were immune to the plague, because some time after visiting the occupied Earth, the Doctor had spread a counter-virus conferring immunity, to make sure that there would be humans left to help him.

At the same time Earth was decimated by the plague, the Daleks attacked human colonies on Azure, Sifranos, Qartopholos and other worlds, though at the time the identity of the attackers was not known. This was done to make sure that Earth could not expect help from these colonies. (NA: Lucifer Rising)

Invasion
At some point, New York City was completely destroyed. London on the other hand, though one of the locations the Daleks landed, was merely occupied and remained relatively intact. (DW: The Dalek Invasion of Earth)

Earth under Dalek rule
The Daleks held the Earth for about ten years. During the occupation period, small groups of human resistance fighters continued to exist.(DW: The Dalek Invasion of Earth) The Daleks operated a blockade of the Solar system to prevent Earth's colonies from attempting to liberate their homeworld. The colonies experienced many problems from the occupation, as they were dependent, to a degree, on communication with and support from Earth. (NA: GodEngine, Lucifer Rising)

The Daleks commenced a mining operation in Bedfordshire in order to reach the Earth's magnetic core, replace it with a propulsion system, and turn the whole planet into a massive spacecraft. (DW: The Dalek Invasion of Earth)

Liberation and aftermath
In the late 2160s, the Daleks announced that they would destroy London. A freedom fighter named Dortmun, who had been developing explosives, initiated an attack on the Daleks' saucer at the London helipad. Although the attack liberated several prisoners of the Daleks, the bombs did not work effectively against the Daleks, leading to several casualties. Ian Chesterton, who had accompanied the freedom fighters, remained on the saucer as it travelled to Bedfordshire.

Following the saucer attack, the First Doctor, his granddaughter Susan and some of the resistance fighters who had been based in London (including David Campbell) travelled to the site of the Daleks' mining operation at Bedfordshire. Barbara Wright and Jenny also (independently) made their way to Bedfordshire, but were captured. They all, however, assisted in the final destruction of the centre of Dalek operations on Earth. In the aftermath, the Daleks withdrew from the planet. The Doctor's grand-daughter, Susan Foreman, decided to remain in this time period with David. (DW: The Dalek Invasion of Earth)


 * The exact year of the liberation was never stated, though an account that the Daleks had occupied the Earth for about 10 years would place it in 2167 or 2168. It was most definitely after 2164, as the First Doctor and Ian found a calendar from this year in an abandoned building in London.

Forced by Davros to reveal to him the Daleks' future defeats, the Fourth Doctor recounted an invasion of Earth, possibly an inaccurate version of these events. He stated that the invasion occurred in the year 2000 and that the magnetic properties of Earth's core itself helped to defeat the Daleks, as well as the determination of human resistance fighters. (DW: Genesis of the Daleks)

Alternate timelines

 * In a divergent timeline, a Dalek in 2158 Kansas, severely damaged by resistance forces, was stung by a parasitic wasp and implanted with eggs. The Daleks adjusted with a minor genetic change to counteract the eggs. Thousands of years later the genetic change resulted in the Mutant Phase, transforming the Daleks into nearly indestructible interstellar insects. The timeline was destroyed when the Fifth Doctor stopped the Dalek Emperor from implementing an ineffective pesticide. (BFA: The Mutant Phase)

Behind the scenes

 * The non-canonical film Daleks' Invasion Earth 2150 A.D. gives a somewhat different account of these events.
 * The invasion possibly occurred during an earlier period of Dalek history, as the Daleks at this point had receiver dishes built into their casings to receive broadcast power for their survival. Other Daleks had relied on static electricity in the floors of the Dalek City. (DW: The Daleks)
 * According to non-narrative material in DWBIT 1, six months after the initial incident, in 2158, the Daleks landed saucers on Earth. The Black Dalek led from the Command Saucer. One of these saucers attacked London. The British government put all their best defences into battle against the Daleks, sending the Air Force's helicopters and fighters to attack the Dalek ship. Tanks fought across the streets, and the Navy fought with gunboats. The humans were persistent, destroying many Daleks, but in a matter of days the Daleks subjugated the humans and converted the most intelligent into Robomen.