Last Great Time War

For Time Wars in general, see Time war.

The Last Great Time War (often called simply the Time War) was the war between the Time Lords and the Daleks, which destroyed Gallifrey and Skaro leaving few survivors.

The War

Origins of the War

The precise facts of the Time War are mostly a mystery, but its origins are slightly more clear. At one point, the Time Lords predicted that in one possible timeline, the Daleks would "destroy all other life forms and make themselves the dominant creature in the universe". The Time Lord Ferrain sent the Doctor on a mission to Skaro during the Thousand Year War with certain objectives:

If possible, to avert the creation of the Daleks
Otherwise to alter their development and make them less aggressive
Find some intrinsic flaw or weakness to exploit in the Daleks

The Doctor believed he managed only to, perhaps, set back the history of the Daleks for a thousand years. (DW: Genesis of the Daleks)

The Daleks eventually learned of what the Time Lords tried to do, and planned to infiltrate the High Council of the Time Lords with duplicates. (DW: Resurrection of the Daleks) One of the Dalek Puppet Emperors opened declaration of hostilities; although the Daleks claimed that these were merely in retaliation for the Time Lords sending the Doctor back in time to prevent their creation.

Later, the Doctor used the Hand of Omega to apparently destroy the Dalek homeworld of Skaro at some point in its history (DW: Remembrance of the Daleks), although he later learned that he may have destroyed a decoy instead (EDA: War of the Daleks).

The Etra Prime Incident (BFA: The Apocalypse Element) began an escalation of hostilities. Lady President Romana made diplomatic overtures. (NA: Lungbarrow) She later initiated a Dalek-Time Lord peace treaty under the Act of Master Restitution. (DWA: 2006 Doctor Who Annual)

This Act enabled the Doctor to safely visit Skaro to retrieve the Master's remains. (DW: Doctor Who: The TV Movie)

The Main War

The war lasted for years and took place throughout space and time. As the Doctor said, "A war with the Daleks against the Time Lords, and the whole of creation at stake." (DWA: 2006 Doctor Who Annual)

The Daleks, wielding the full might of the Deathsmiths of Goth, launched a massive fleet into the Time Vortex, launching the war. (DWA: 2006 Doctor Who Annual) The main force was made of a fleet of Dalek Flying Saucers. Over a million Battle TARDISes were used by the Time Lords, (NSA: Peacemaker) though Bowships, Black Hole Carriers and N-Forms were also used (DWA: 2006 Doctor Who Annual).

The Time Lords also resurrected the Master, believing him to be an excellent soldier. The Master was to protect the Cruciform, but when the Dalek Emperor took control of it he ran in fear. (DW: The Sound of Drums)

During the very first year Davros was killed at the Gates of Elysium, when his command ship flew into the jaws of the Nightmare Child. The Doctor tried to save him, but failed. Eventually, Caan, a survivor of the war managed to time shift back into the war and extract him from the time-locked event, at the cost of his sanity, transporting him into the post-war universe. (DW: The Stolen Earth, Journey's End)

During the course of the war, the entire chain of Hotel Historias was destroyed (DWM: Hotel Historia) and the Nestene Consciousness's protein planets, including Polymos, were destroyed. (DW: Rose, TDL: The Dust of Ages) Another of the known theatres was Arcadia, where main Arcadia fell from the sky and the Doctor fought on the front lines that eventually fell to the Daleks. (DW: Doomsday)

The Doctor attempted to regain the Great Key, which had been stolen by unknown forces. After being imprisoned for a month, with the help of Chantir he was able to escape with the key. With the key, he believed that the De-mat Gun could be replicated and the Medusa Cascade closed. The Doctor planned the modify the gun so that instead of it removing an individual from time and space, he planned to make it remove millions from time and space. (IDW: The Forgotten)

Toward the end of the war the Daleks sent a capsule to 70 AD Earth in order to spread the Dalek Factor amongst Humans. The capsule's engine exploded, and the Dalek was killed soon after impact. It was only able to release a small amount of the Dalek Factor, leading to only one in 0.5 million Humans having it. (NSA: I am a Dalek)

Conclusion

During the last act of the Last Great Time War, Gallifrey, many planets, star systems and even galaxies were destroyed in a single instant. (IDW: Agent Provocateur) Gallifrey itself was destroyed when the Cruciform fell. (IDW: The Forgotten) With the exception of a few survivors, both the Time Lords and the Daleks disappeared from time and space.

It is also known that the planets Gallifrey and Skaro themselves were destroyed. The Doctor implied that he played a major part in finally destroying both sides. (DW: Dalek). It is because of this that the Beast referred to the Doctor as "killer of his own kind". (DW: The Satan Pit) The Doctor stated "when I turned the Key in the lock I doomed them all". (IDW: The Forgotten)

At some point in its course, the war became time-locked, making it (in theory) impossible to revisit the events; Dalek Caan, however, was somehow able to do so, but at the cost of "his" sanity. (DW: The Stolen Earth) This is probably why the Doctor was unable to go back and save his people (as hinted at in DW: The Fires of Pompeii), although he has hinted that the idea occurred to him. (DW: Father's Day)

Aftermath and aftershocks

The war was mostly invisible to "lower species", but devastating to the time-aware "higher" ones. The Time Lords were thought of as myths for the higher species, like the Forest of Cheem. (DW: The End of the World, The Stolen Earth)

The Nestene Consciousness justified its 2005 invasion of Earth with the loss of its protein planets. (DW: Rose)
The Gelth lost their physical bodies because of the war, reduced to gaseous forms. (DW: The Unquiet Dead)
The Eternals apparently fled this reality in despair, never to be seen again, and the Greater Animus died in the conflict. (DWA: 2006 Doctor Who Annual)
Though the Sontarans were aware of the war, they weren't allowed to take part (DW: The Sontaran Stratagem), as opposed to the Graxnix who were one of the lowest races allowed to take part in the war. (DWM: Hotel Historia)
It is possible that Eve's Species was wiped out in The Last Great Time War since she mentioned 2 races (The Time Lords and The Daleks) and her Planet being "Exterminated" because her people were time-sensitive (SJA: The Mad Woman in the Attic).

The destruction of the Time Lords created a vacuum that may have left history itself more vulnerable to change. The Doctor explained to both Rose and Donna Noble that time was in flux and history could change instantly-- a big change from the way it had been. (DW: The Unquiet Dead, The Fires of Pompeii)

The most dramatic demonstration of this was when Rose created a temporal paradox by crossing her own time stream to save her father's life just before his intended death in a traffic accident. This summoned the Reapers, who descended to sterilize the "wound" in time by devouring everything in sight. The Doctor stated that if the Time Lords had been still around, they could have held back the Reapers and prevented or repaired the paradox. (DW: Father's Day)

As well, the Doctor noted that when the Time Lords were around, travel between Parallel worlds was less difficult. With their demise, the paths between worlds were closed. (DW: Rise of the Cybermen)

Known Survivors

The Dalek Emperor, one of the survivors of the war (DW: The Parting of the Ways)

Time Lords

The Doctor survived. He stated that if any other Time Lords lived, he would have sensed their presence. (DW: Dalek)

The Doctor's survival may have entailed a regeneration. Though he did not say so categorically, he implied unfamiliarity with his new face when he first met Rose Tyler; it's not known, however, how much time elapsed between the end of the war and his first meeting with Rose.

The Master also survived, having used a Chameleon Arch to become the Human Professor Yana in order to escape the war. His use of the arch prevented the Doctor from sensing his existence. (DW: Utopia)
Whilst not a Time Lord, Leela was a resident of the Capitol on Gallifrey, and it is known that she survived, at least for a small time, after the destruction of Gallifrey. (CC: The Catalyst)
Again, while not a Time Lord, K-9 Mark I may have survived the destruction of Gallifrey before travelling through time to the year 2050 and 'regenerating'. K-9 TV series

It has yet to be confirmed exactly when K-9 left Gallifrey; it may have occurred at some time before the war.

Daleks

A lone Dalek survived and crashed onto the Ascension Island on Earth in 1962 (DW: Dalek)
The Dalek Emperor also lived, although he had fallen through time to approximately the 2,000th century and set about re-building an army from the DNA of Humans. (DW: Bad Wolf)
The Cult of Skaro and the Daleks imprisoned within the Genesis Ark escaped the attentions of the Bad Wolf, having left the universe for the Void before the end of the war. (DW: Doomsday)
Though Davros was believed by the Doctor to have been killed in the war, Dalek Caan was able to temporal shift into the war and rescue him. (DW: The Stolen Earth, Journey's End)

Others

As Eve's Species were Time-Sensitive The Daleks Exterminated their homeworld. Eve's parents sent on a ship to escape, she eventually landed on Earth (SJA: The Mad Woman in the Attic).

Behind the scenes

A 2005 faux-documentary produced by BBC Radio, The Dalek Conquests, attempts to put the Time War into context with the Doctor's recurring conflicts with the Daleks over the years.
A long-running story arc featured in the BBC Eighth Doctor Adventures book series concurrent with the return of Doctor Who to television in 2005, featured a Time War between the Daleks and Time Lords. Russell T. Davies, producer of the revived TV series, has, however, been on record as stating that the Time War featured in the books is a different conflict, which is one reason why the battle referenced on TV is often referred to as "the Last Great Time War".