2150s Dalek invasion of Earth

The 2150s Dalek invasion of Earth, sometimes known as the First Dalek War (PROSE: Prelude Deceit) was a conflict between humanity and the Daleks, consisting of Dalek attacks on human colonies followed by a decade-long occupation of Earth in the 2150s and 60s. (TV: The Dalek Invasion of Earth, etc.) To the Daleks, the invasion was a means for Project Degravitate. (PROSE: Doctor Who and the Dalek Invasion of Earth, AUDIO: The Dalek Conquests)

Whilst being aware of an reconnaissance scout mission 1,300 years earlier, the Time Lords regarded the 22nd century attack as the "first attempt" and the "initial invasion" of Earth from the Daleks' perspective. (PROSE: Dalek Combat Training Manual) According to some other accounts, the Dalek invasion took place in the 21st century. (TV: Genesis of the Daleks, PROSE: Doctor Who and the Crusaders, The Evil of the Daleks)

One dissenting account stated that the Daleks invaded Earth in the year 2164. (PROSE: The History of the Daleks) According to another account, it was in that year that the Earth was liberated. (AUDIO: Masters of Earth)

Foreseeing
In 1903, after receiving a wealth of information from the future, Grigori Rasputin foresaw, among other things, the First Doctor, Ian Chesterton, Barbara Wright and Susan Foreman battling "strange beings" who had invaded Earth in the future. (AUDIO: The Wanderer)

Origins
According to one account, the early Daleks knew of the existence of other planets even though a lack of space travel confined them to Skaro. When Kest, a Krattorian slave trader, landed on the planet, the Daleks were able to acquire from him the plans to create their own spacecrafts. (COMIC: Power Play) Going with a flying saucer design, the Daleks invaded Alvega, (COMIC: The Amaryll Challenge) Solturis, (COMIC: The Penta Ray Factor) and Phryne, (COMIC: The Archives of Phryne) with plans for other planets such as Oric. (COMIC: Eve of War) According to another account, the Daleks first learned about life existing on other worlds due to the First Doctor's visit to Skaro. (AUDIO: The Lights of Skaro) By this telling, the Daleks may have targeted earth because the Doctor's companions, Ian Chesterton and Barbara Wright, were the first aliens they encountered.

The existence of Earth, however, managed to elude the Daleks for a time, the planet long being their blind spot. (COMIC: Legacy of Yesteryear, The Road to Conflict) Nevertheless, they did know of the existence of humans and tensions began to rise. In one instance, a Dalek created with human-like qualities seized control from the Dalek Emperor and began to teach the Daleks that beauty was a strength. To solve the problem, the Emperor likened the strength of beauty to flowers, which withered and died. Beauty therefore did not last which meant it could not be a source of strength and was for human beings. The Emperor had the rebel Dalek destroyed and issued a new Dalek order, stating that humans were to be destroyed. (COMIC: Shadow of Humanity) The Daleks also faced what they called the human spirit in the humanoid species from the planet Jevo. Although they were destroyed, the Emperor wondered how the Daleks would fare against such a resilient spirit in "the all-out war on all human beings... everywhere." (COMIC: The Emissaries of Jevo)

Long following the mid-22th century invasion from the Daleks' perspective, they would attack Earth on several occasions earlier in its history, most noticeably in the early 21st century Dalek invasion. However, the Time Lords were aware that Big Bang Two caused subtle changes in Earth's timeline which would remove the memory of incidents such as this invasion; as such, humanity at large would still be ignorant of the Daleks. (PROSE: Dalek Combat Training Manual) Indeed, most humans were left unable to remember that the aliens had invaded their world, though one theorist, whose memories of the Daleks from the Battle of Canary Wharf were vague despite his clear memories of the "steel soldiers" present on that day, found that their friends, briefly, had slight recognition on their faces whenever he described the battle, only for their friends to lose that recognition in seconds. (PROSE: The Mandela Effect, Or Monsters on the Streets of London)

Humanity remained unaware the Daleks were plotting against them. By the late 21st century, humans had experienced the Break-out and possessed a number of colonies beyond Earth. (PROSE: Prelude Deceit) Years prior to the invasion, (PROSE: The Power of the Daleks) the human colonists on Vulcan were threatened by a smaller-scale Dalek attack. (TV: The Power of the Daleks) However, by 2136, both Vulcan and the Daleks were considered little more than legends. (PROSE: The Murder Game)

An Earth-made ship, the Starmaker, was pounded by a meteor storm and forced to land on Skaro. The Daleks destroyed the ship. The only survivors were Captain Flint Fleet and two children, siblings Tom and Jennie, who escaped in a Dalek saucer to warn Earth of the danger posed by the Daleks. Among the wreckage of the Starmaker, the Daleks found the remains of a piece of paper which revealed to them the existence and location of Earth. The Emperor declared that the Daleks would search for Earth and conquer it. (COMIC: The Road to Conflict) When the Daleks first ventured into the Sol System, their fleet was initially repelled by Earth forces led by Commander Trent with the help of the Elders. The Emperor, the Black Dalek and the Red Dalek escaped and resolved to return. (COMIC: Return of the Elders)

Colony attacks
The Dalek Emperor on Skaro formulated the plan for the invasion of Earth and its subsequent transformation into a planet-sized spaceship, choosing Bedfordshire as the area for the primary mining operations meant to drill into the Earth's core and replace it with an interstellar engine. Once the plan was complete, he gave the order to begin the invasion of Earth. (AUDIO: The Mutant Phase)

The invasion began in 2157 with mysterious attacks on Sifranos in the Arcturus sector (a moon of Sifranos was destroyed, one billion settlers being massacred), Azure, Qartopholos, (PROSE: Lucifer Rising) and Mars. (TV: Genesis of the Daleks) These were followed by the plague attacks directly on Earth while the Dalek Fleet massed near Epsilon Eridani. With the colonies destroyed, Earth could expect no assistance from them when the Daleks invaded Earth in 2158. (PROSE: Lucifer Rising) 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. (PROSE: GodEngine, Lucifer Rising)

Later in 2157, the Daleks attempted to invade Mars. However, the inhabitants developed a genetically-engineered virus that attacked their spacecrafts' wiring, meaning that this invasion attempt had failed. (TV: Genesis of the Daleks, PROSE: GodEngine)

Earth's invasion
The first incident of the invasion came in 2157, (PROSE: Lucifer Rising) 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. (TV: The Dalek Invasion of Earth)

Some humans were immune to the plague, because the Seventh Doctor had given to Piper O'Rourke a counter-virus that conferred immunity to make sure that there would be humans left to help his first incarnation defeat the invasion. (PROSE: Lucifer Rising) With the Earth now heavily weakened, the Daleks arrived to complete their conquest, with humanity unable to respond with any power as Dalek flying saucers filled the skies. (PROSE: Dalek: The Astounding Untold History of the Greatest Enemies of the Universe)

The Terran Security Forces were easily defeated by the Daleks, (PROSE: The Final Sanction) who arrived in their flying saucers to reveal the Earth was outgunned. Quickly, the Daleks moved to wipe out the Earth's politicians, exterminating many in Parliament Square in London. After the Daleks demanded the planet surrender, some politician locked themselves away in the Houses of Parliament in an attempt to remain safe, only to be burned alive when the Daleks lit the buildings ablaze. (PROSE: Alien Bodies) The Houses of Parliament were left abandoned. (AUDIO: After the Daleks)

Iris Wildthyme visited Putney Common during the invasion. A Dalek saucer landed on the Common, Iris and her friends were among the first to throw homemade bombs at it. (PROSE: From Wildthyme with Love)

At some point, New York City was completely destroyed. London, on the other hand, though one of the locations where the Daleks landed, was merely occupied and remained relatively intact (TV: The Dalek Invasion of Earth) despite losing most of its population. (PROSE: Alien Bodies) Additionally, the city suffered some of the worst attacks since the Blitz and the 1944 V1 and V2 attacks by the Nazis during World War II, with the Daleks reducing many areas to gravel. (PROSE: Illegal Alien) Some areas of the city became infested with wolves, with a "danger zone" being identified wherein it was unsafe to live. (PROSE: When the Wolves Came) St Paul's Cathedral survived the invasion as well as the first four world wars. (AUDIO: Frostfire)

Occupation
With Earth conquered, the majority of the Daleks departed, leaving a comparatively small Dalek Earthforce behind. Assisted by the Robomen, (PROSE: The Whoniverse) the Daleks held the Earth for about ten years. During the occupation period, small groups of human resistance fighters continued to exist. (TV: The Dalek Invasion of Earth) A Red Dalek had authority over the Silver Dalek drones in Trafalgar Square and personally led patrols. An older Susan Foreman once arrived in the occupation while travelling in the Doctor's TARDIS. She escaped but was followed through time by a Blue Chrono-Dalek deployed after her by the Red Dalek. (TV: Susan and the Daleks)

In occupied London, the Daleks raided the Ministry of Defence vaults and scanned their records for the Daleks as a matter of precaution, considering the possibility that the humans had developed stealth weapons to be used against them. Though they found no such weapons, they became aware of two human contacts with the future Daleks, the Styles business and the Hand of Omega, which would destroy Skaro after it was acquired by Davros. The Daleks, who had believed that Davros was dead, were concerned by this revelation. (PROSE: War of the Daleks)

The Sixth Doctor and Peri Brown landed in 2163. The Daleks were unfamiliar with the Doctor, thinking he was a human. The Doctor was interrogated by a Black Dalek. He foiled the Daleks' plan to unleash a Varga plant virus. The Doctor and Peri also defeated the Roboman Elite and erased any record of his involvement afterwards but the invasion continued to ensure the First Doctor finally put an end to it. (AUDIO: Masters of Earth)

Liberation
As they had always planned to, (PROSE: Thw Whoniverse) 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 to conquer the galaxy. (TV: The Dalek Invasion of Earth)

In 2167, (AUDIO: The Mutant Phase) the First Doctor and his companions arrived in occupied London. Shortly afterward, the Daleks announced that they would destroy London. The leader of the rebels of London, Dortmun, had been developing explosives and initiated an attack on the Daleks' saucer at Helipad Chelsea. 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 Dalek Supreme Command issued an order for the destruction of what remained of London using firebombs. One of these firebombs was placed near one of the resistance base entrances, which the Doctor, Susan and David Campbell were hiding beside. David spotted the bomb soon after, and was able to disable it by using acid from Dortmun's bombs to burn through the casing and remove the internal mechanism of the firebomb. Some of the resistance fighters, including the Doctor, Susan, and David, from London to the site of the Daleks' mining operation at Bedfordshire. Barbara Wright and Jenny also, independently, made their way towards Bedfordshire, but were captured.

They all, however, assisted in the final destruction of the centre of Dalek operations on Earth, with Barbara taking control of Dalek communications to order the Robomen to turn on their masters. Robomen and slaves alike rebelled against the Daleks, who were left immobilized in their tracks after the Doctor overloaded their systems, while the command saucer was destroyed by lava as the mining operation collapsed. (TV: The Dalek Invasion of Earth) Some did display the ability to move but without control, leaving these Invaders to scream and plead for help from within their shells until they crashed and died. (PROSE: A Star's View of Caroline) Quickly, the surviving Daleks withdrew from the planet. Susan decided to remain in this time period with David. (TV: The Dalek Invasion of Earth)

Iris Wildthyme once claimed she had ended the invasion with her companion Jeremy. (PROSE: The Scarlet Empress) According to one account, the First Doctor and Susan had also disarmed a bomb in London during their time fighting the invasion. The Twelfth Doctor and Clara Oswald wound up during the events of the invasion after they jumped into a portal created by a time fly at the hands of Ethel. They were chased by time flies and Daleks, equipped with bronze casings, alike but were able to explode them using the bomb. (COMIC: A Stitch in Time)

Aftermath of the first invasion
The remains of the Invaders littered the cities they had once occupied; with their flabby bodies left dead and falling to dust, their metal shells were left rusted and cracked, leaving the Invader's remains open for humanity to wreck in revenge. (PROSE: A Star's View of Caroline) One Dalek survived the invasion and bargained with former collaborator Marcus Bray to deliver it to a Dalek flying saucer so it could escape, only for him to publicly execute it to win favour with the humans. Bray then led a witch hunt against Susan Foreman, only for her and her allies to trick him into revealing his working for the Daleks. Following Bray's death, Susan set the saucer to self-destruct. On a broad scale, it was estimated that the invasion had sent Earth's technological development, including the development of time travel and ganger technology, back 200 years. (AUDIO: After the Daleks)

The invasion killed about two-thirds of Earth's population. The Moonbase was cut off from the planet and the moon colonists were trapped on the satellite. About twenty years later the liberation, humans had grown xenophobic about aliens, rejecting Dalek technology in public burnings and regressing the level of the planet's technology by about two centuries. An Earth Council was in charge, handling the reconstruction. (AUDIO: An Earthly Child) Whilst many communities active throughout the Invader's occupation had survived using fear and despair to fuel their actions, those who started to rebuild the Earth after a decade of being under occupation found relics of their past society, including charred buildings, machines that were half broken, adverts for cereals, calendars, and human remains. (PROSE: A Star's View of Caroline)

In 2169, Homunculette and Marie visited the ruins of the House of Commons to buy the Relic from the Black Man, who was selling remnants from the Toy Store. (PROSE: Alien Bodies)

P.J. Ring became a Revelator and later a saint after being exposed to the Source during the end of the invasion. Also present during this time was a woman going by the name "Caroline", who had previously been to the Invader's homeworld and been brought to this century by her "grandfather". She reflected that "one day" she "[would] get back" to him. She also encountered two temporal uncertainties, going by the names Homogeny and Hegemony, who tried to use her to become "certain" in time. (PROSE: A Star's View of Caroline)

During the invasion, humans dumped a lot of their dead into the River Thames, leaving the corpses as food for the blackwater parasites. Two years after the end of the invasion, the river was still filled with chemical sludge (PROSE: Alien Bodies) and sticky red algae that the Invaders fed to their aquatic pets. Even decades later, the Thames was still completely abandoned. (PROSE: A Star's View of Caroline)

Survival became increasingly difficult due to wild animals roaming the streets. Simon encountered a pack of wolves on the streets when scavenging for food, but survived by finding the TARDIS and using its telepathic circuits to seek help from the Twelfth Doctor and Clara. (PROSE: When the Wolves Came)

With the Daleks gone, humans on Earth fought amongst themselves in the Intercity Wars which "sparked and spat" across the planet for decades until volunteer members of Earth's nearest colonies returned to bring it back into order by force. (PROSE: The Janus Conjuction)

Reprise
In the late 2180s, the Dalek Time Controller organised a second invasion of the planet. The Daleks were helped by the Time Lord known as the Monk, who brought on Earth a plague that killed and affected a number of people. The Monk was promised to be allowed to plunder the art treasures of the planet in return for his technical expertise. The Monk made three major contributions to the invasion; firstly, he repaired the Dalek Time Controller when it was blasted back through the Time Vortex, and was in a state of decay beyond the Daleks ability to repair. Secondly, the Monk was personally responsible for unleashing a virus into Earth's atmosphere which was beyond the humans' ability to stop it, killing millions and weakening the planet ready for the upcoming invasion. Lastly, the Monk provided the resistance with the technical ability to hack into Dalek transmissions during a final attempt to end the invasion, but he betrayed them to the Daleks.

The master plan was to pilot the Earth with a time warp engine, which would have become a plague planet teeming with the Amethyst viruses, through time and space, infecting entire planets. The invasion was stopped by the Eighth Doctor, thanks to the sacrifice of Lucie Miller and Alex Campbell. (AUDIO: Lucie Miller / To the Death)

Legacy
The events of this invasion were recounted in the book, The Rise and Fall of Earth's Empire, by Layten Halkovich. (PROSE: The Secret Lives of Monsters) In the post-Time War universe, this incident was covered as a part of known Dalek history in The Dalek Conquests, a documentary which was itself produced following the Van Statten Incident on Earth in 2012. (AUDIO: The Dalek Conquests)

News of the Daleks' repulsion from Earth quickly spread across the Dalek Empire, leading other subjugated races to rise up against the Daleks. (PROSE: Dalek: The Astounding Untold History of the Greatest Enemies of the Universe) Following the liberation of Earth, the Daleks began to use Robomen less after their heavy use on the occupied planet failed to prevent the human victory. (PROSE: The Dalek Problem)

According to the Dalek Survival Guide, it was following the failure of the 2150s Dalek invasion of Earth that the Daleks began using Ogrons as shock troops; the guide suggested that the Ogrons' natural stupidity made them easier to control than humans and so eliminated the need for the time-consuming robotisation process. (PROSE: Dalek Survival Guide) Indeed, the Ogrons were serving the Daleks by the time of Operation Divide and Conquer in 2540, (TV: Frontier in Space) and in their time travel-based occupation of 22nd century Earth. (TV: Day of the Daleks) The use of Ogrons in fact originated in the later Last Great Time War, the Overseer having inserted them into pre-Time War Dalek history. (AUDIO: Planet of the Ogrons)

The Daleks eventually identified the First Doctor and his companions and discovered their key role in "delay[ing]" the conquest of Earth. A squad of Daleks embarked from Skaro in a time machine on a mission to assassinate them. (TV: The Chase) The Time Lords indicated that the deployment of the time machine occurred relatively shortly following the liberation of Earth, within the 22nd century. (PROSE: Dalek Combat Training Manual)

Forced by Davros to reveal to him the Daleks' future defeats during the Genesis Incident, 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. (TV: Genesis of the Daleks)

In 2199, a Dalek research facility, DA-17, remained intact. The Eighth Doctor and his granddaughter Susan were trapped along with and new Daleks were produced by the hatchery. They attempted to conquer England but were destroyed when DA-17 exploded. By this point, there were still Slythers in the forests around London where they would attack anyone who wandered into their paths. Dedicated knights hunted and killed them. (PROSE: Legacy of the Daleks)

In the aftermath of the invasions, many humans remained paranoid about another alien incursion and took to carrying weapons on their person. (AUDIO: All Hands on Deck)

Following the second invasion, Susan made her home in a block of flats which had once been Coal Hill School. Despite the Doctor's efforts to distract her, Susan found that she had been sent Hypercube messages from the Time Lords, who were engaged in a time war against the Daleks. Citing her participation in the resistance against the two Dalek invasions on Earth as well as reasoning that the Daleks would ultimately return should the Time Lords fall, Susan decided to accept their request and join the war despite the Doctor's protest, summoning a TARDIS to collect her. (AUDIO: All Hands on Deck) By another account Susan was still on Earth fifty years after the invasion, encountering the Thirteenth Doctor as she was on her way to a pyre of Dalek technology. The Doctor showed her the remains of a dead Dalek, shich Susan could take out her anger on. (PROSE: Fellow Traveller)

By the beginning of the 23rd century, the invasion remained a source of much anxiety on Earth as governments tried to rebuild. With government approval, a powerful cartel of Earth conglomerates offered to rebuild and invest in the Terran Security Forces which grew into a huge army within five years. This army was used to combat the Selachians when their expanding power on the galactic market threatened that of Earth, and by 2204, they had all but destroyed the last outposts of the Selachian Empire. (PROSE: The Final Sanction)

By one account, mankind had regained their former strength within fifty years of the liberation of Earth. (PROSE: The History of the Daleks)

By 2233 corporations dominated Earth, whilst fear of a new invasion drove new scientific research, such as that conducted by Drake Interplanetary. The ruins of St Paul's Cathedral had been pulled down by this time which Magnus Drake disagreed with, believing it should have stood as a monument to how close humanity had come to destruction. In April, manipulated scientist Lila Kreeg to release him from the Time Vortex. With her aid he took over Drake Interplentary, (AUDIO: Faustian) and turned it into the most powerful company on Earth. (AUDIO: Prey)

In 2233, the Daleks returned to Earth. A single saucer landed in London under the command of a Dalek Supreme, accompanied by the Dalek Litigator who was using the invasion to hunt down. The Master massacred the Daleks, such that the Litigator contacted the Dalek Parliament who ordered the invasion be abandoned. The Master killed the Supreme and forced the Litigator to flee by temporal shift, taking the saucer for himself and planning to use it to devastate Earth as he departed. He was stopped by Lila and Vienna Salvatori who sent the saucer, and the remnants of its Dalek crew, into the Time Vortex with him onboard. (AUDIO: Vengeance)

Vicki Pallister learned about the invasion from the history books in her native time period of the 25th century. (TV: The Space Museum, The Chase)

In 2540, the Daleks waged another war against humanity and made a push for Earth's solar system five years later. Though the Daleks briefly seized Mars, only a few biogenic weapons managed to get as far as Earth. Ultimately, the Daleks failed to launch a new Earth invasion before they pushed back to their own space. (PROSE: Beige Planet Mars)

By Steven Taylor's native time period, New York City had yet to be rebuilt in its entirety. (PROSE: Salvation; AUDIO: Return of the Rocket Men)

In the year 4000, Gordon Lowery was aware that the Daleks had invaded Earth "a couple of times, and were beaten back" before leaving the galaxy a thousand years or more earlier. (PROSE: Mission to the Unknown, TV: Mission to the Unknown) That year, when the Dalek Empire sought to strike from Kembel and destroy the Solar System, the First Doctor urged Bret Vyon to contact Earth and tell them to look into the invasion of 2157, hopeful that history would show them the way to defeat the Daleks again. (TV: The Daleks' Master Plan)

After their memory of the Doctor was wiped from the Pathweb for a time, the Daleks forgot, amongst other incidents, who had liberated Earth in the 22nd century. (PROSE: Dalek: The Astounding Untold History of the Greatest Enemies of the Universe)

Alternate timelines
In a divergent timeline, a Dalek in Kansas in 2158, 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. (AUDIO: The Mutant Phase)

In a timeline created in which used a conceptual bomb to prevent the Doctor from leaving Gallifrey, the Dalek occupation was never repelled. (AUDIO: The Light at the End)

Behind the scenes

 * Published in 1991, The Terrestrial Index stated that the plan for the 22nd century Dalek invasion started in 2160 with the Dalek Plague before the Daleks conquered Earth in 2164, with the planet ultimately being liberated in 2167. This conflict is identified as the First Dalek War, the first of a series of human-focused Dalek Wars, followed by the Second Dalek War, the Third Dalek War, and the Fourth Dalek War.
 * Masters of Earth dates the invasion between the years 2154 and 2164 (with the initial meteor bombardment occurring circa 2152) based on the calendar the Doctor and Ian find in The Dalek Invasion of Earth. Additionally, Ben remembers the Doctor mentioning the invasion of 2164 in the audio story The Forbidden Time. This is at odds with the dating in Lucifer Rising of the invasion in the ten years between 2157 and 2167, and with the title of the Peter Cushing version of the story, Daleks' Invasion Earth 2150 A.D., which evidently posited that the invasion took place in the year 2150 (although this latter source is not a valid source on this Wiki).
 * 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. It also stated that the Doctor’s involvement had led to the Daleks retreating.
 * As recounted by Susan Foreman in NOTVALID: Whatever Happened to Susan Foreman?, the invasion was waged by Daleks who had travelled back from the distant future using a TARDIS of their own. Having been defeated on Skaro by the Thals led by Ian Chesterton, their intent was to wreck revenge on Ian's people or, better still, prevent Ian himself from being born by going into the past. However, they were unable to go any further back than 2164 due to a leak in their fluid link.
 * The Discontinuity Guide also claimed this was "mankind's first major encounter with the Daleks", following the earlier Vulcan Incident, took place in 2164. Following their defeat, the Daleks' completed their time travel program and successfully invaded Earth in the late 21st century, only for their work to be undone by the Third Doctor. It is further noted that, since the Fourth Doctor inadvertently changed Dalek history so that Davros survived, this event would have occurred vastly differently if it happened at all in the new timeline. Other sources disagree on whether the Fourth Doctor's actions altered time.
 * The third edition of AHistory speculates that the events of Legacy of the Daleks became an alternate timeline when and the Dalek Time Controller rewrote history to enable a second Dalek invasion in the 2180s, as seen in Lucie Miller and To the Death, but admits that this doesn't explain how Susan can have a child with David, or how the Master ended up on Tersurus in.
 * The Dalek Handbook suggests that, if the Doctor was truthful in saying that he set back Dalek history a thousand years, then Earth would not have been invaded until 3157 in the new timeline.