There was an early 20th century counterpart, called LONGBOW. This world security organisation was set up by the UN precursor, the League of Nations. LONGBOW dealt with the occasional extraterrestrial incident, but was disbanded after it, and the League, failed to prevent World War II.
The roots of the organisation itself, however, lay in previous alien encounters. The Intrusion Countermeasures Group headed by Group Captain Ian Gilmore, which got involved in the Shoreditch Incident, served as a specialised military force with scientific assistance would seem almost a trial run for UNIT, though not an international organisation. Though Gilmore did have two scientific advisors (serving a function much like third incarnation of the Doctor and Dr. Elizabeth "Liz" Shaw would serve later), the seventh incarnation of the Doctor did most of the work, here, on the technical end.
A second significance was the takeover of London by the Great Intelligence, using robot Yetis and a deadly cobweb-like fungus. Assisted by the Doctor, another group of British infantrymen, led this time by Colonel Alistair Gordon Lethbridge-Stewart of the Scots Guards beat back the Yeti from the tunnels of the London Underground. UNIT themselves would later consider this to be the main origin of the organisation.
The United Nations was by now ever more aware that the world faced threats from extraterrestrial sources and that with the space programme sending probes deeper and deeper into space, mankind had drawn attention to itself. Unable to get the British government to form a permanent special operations force for alien threats, Lethbridge-Stewart went over their heads to the UN Security Council, who proved more receptive. The UN established UNIT with the mandate to investigate, monitor and combat such threats. At the suggestion of Gilmore from the ICMG, Lethbridge-Stewart was promoted to the rank of Brigadier and put in charge of the British contingent, organisationally known as Department C19 within the British government.
The Lethbridge-Stewart yearsEdit
One of UNIT's first missions was an intensive investigation of International Electromatics; this turned violent, with UNIT agents being eliminated during investigations and UNIT itself launching a helicopter raid to liberate prisoners at an Electromatics' facility. With the help, again, of the Doctor, UNIT discovered the company was a front for a Cybermen invasion and was able to defend against it..
Following this, Lethbridge-Stewart became convinced of the necessity of scientific advice in battling extraterrestrial threats, and recruited Liz Shaw from the University of Cambridge. Coincidentally, the Third Doctor, had been exiled to Earth by the Time Lords. The Doctor agreed to join UNIT as its Scientific Advisor just in time to help defeat the Autons.
After this the doctor continued to assist them for a while. He and Liz helped UNIT fight aliens such as The Silurians and the Primords. After this Liz Shaw left UNIT.
Liz Shaw was replaced by Jo Grant as the Doctor's scientific assistant. Though she only managed to get her A levels in Science. When he met her, UNIT made an enemy out of The Master. But UNIT did manage to lock the Master up after several attempts to destroy UNIT and earth.
When the Doctor's exile was lifted, his association with UNIT became more sporadic, especially after his regeneration into his fourth incarnation.
Though the Doctor did return to Earth with Sarah Jane Smith, he would work less and less with the Brigadier and more with such other officers as Colonel Faraday (the Brigadier having gone to Geneva) and Major Beresford. The Doctor, however, never officially left UNIT.
As a United Nations group, UNIT often saw use as security at peace conferences and the British contingent had foreign soldiers such as Sergeant Zbrigniev.
UNIT would often face hostility in its operations, particularly when investigating research facilities and companies. A common tactic used against UNIT were appeals by administrators to any contacts they had in the Westminster government, which either forced Lethbridge-Stewart to back down or go over the government's heads to Geneva.
Lethbridge-Stewart retired in 1976 and went to teach mathematics at Brendon School. He was succeeded by Colonel Charles Crichton. At some stage, Benton and medical officer Harry Sullivan also left.
The Doctor re-united, in his seventh incarnation, against an invasion by Morgaine and her armoured knights. The British contingent was commanded by a new female Brigadier Winifred Bambera. Lethbridge-Stewart was called out of retirement to assist Bambera and the Doctor. This version of the Doctor would, again, assist the UNIT officer Muriel Frost in the late 1990s in their struggle against the Mandragora Helix.
At some point in the late 20th, early 21st century, a book on the history of UNIT was published (though it's not known how much if any information on the organization's activities is included).
Simultaneously, in the name of "homeworld security", UNIT adopted a questionable attitude towards civil rights and liberties, which the Doctor found disquieting. UNIT maintained a secret prison. Here a small number of detainees could be held without charges needing to be pressed or without the usual rights of prisoners. This suggested UNIT has a somewhat more malevolent side than other recorded encounters may suggest. Among those kept at one time as prisoner by UNIT was Toshiko Sato in 2005 or 2006; she was only released when Jack Harkness and Torchwood Three convinced her to work for them.
In at least the late 20th and early 21st centuries, UNIT maintained a small division based in the United States, led by Brigadier General Adrienne Kramer.
At some stage prior to the 2009 Sontaran invasion, UNIT changed its name from United Nations Intelligence Taskforce to Unified Intelligence Taskforce. UNIT retained its traditional logos, however, even though they displayed the now-technically incorrect initialization "U.N.I.T."
At some point, the UK division of UNIT was facing being shut down and replaced with domestic group ICIS (Internal Counter-Intelligence Service). When it became clear ICIS were brutal and dangerous, Lethbridge-Stewart and Colonel Emily Chaudhry deliberately revealed UNIT's remit to the press (stating UNIT had faced over 200 invasions) and the existence of Silurian ambassadors; while this was viewed as a hoax, it forced the government to leave UNIT in charge of alien matters, leading to uneasy co-existence with ICIS.
Unknown to UNIT, their leader Colonel Brimmicombe-Wood was an ICIS plant who had been deliberately groomed to assume leadership of their rival. ICIS' involvement in an attempted coup and murderous attempts at framing UNIT led to their shutdown, however; in the process UNIT thwarted the coup and stopped a worldwide pandemic, unfortunately losing temporary commander Colonel Robert Dalton in the process. Colonel Chaudry was given command of the UK contingent.
Before 2005, UNIT had been involved in multiple situations without the Doctor, including the Fourth Reich, the Guatemala "big locust" Problem, Operation Plainsong, the Skaniska Incident and the Jersey Tollgate Situation. 2005 saw the organisation increase its New York presence centered around a New York Liason Office, allowing immediate UNIT briefing of the UN General Assembly. They also had been hosting annual conferences for several years. An officer named Major Jenny Maguire had had previous experience with the Doctor, who had annoyed her in unknown circumstances.
In 2005, UNIT sent a delegation to a gathering of experts to 10 Downing Street in response to a spaceship crashing in the River Thames. All of the experts were electrocuted by the family Slitheen. The identities of the advisors killed were not known, although one woman officer bore the name "Frost" on her jacket. By this time, UNIT and the Torchwood Institute were aware of each other. UNIT asked for the assistance of Torchwood Three's Owen Harper during this incident. Toshiko Sato would fill in for him.
In Christmas 2006, UNIT had a command center located in the Tower of London which was under the command of Major Richard Blake. UNIT maintained some contact with Torchwood Three, even after the Battle of Canary Wharf. Torchwood Three's leader, Jack Harkness, would occasionally confer with the heads of UNIT and once asked for and received the help of Martha Jones, a medical doctor and former companion of the Doctor's, who he and the Doctor had suggested for a position with UNIT.
By 2007 UNIT operated a floating aircraft carrier airship, the Valiant, which was mainly designed by British Minister of Defense (actually the latest incarnation of the Master) Harold Saxon.
Sarah Jane Smith remained in friendly contact with UNIT, leading to its involvement in cleaning up a Slitheen plot.
Prior to the 2008 Sontaran invasion, Martha Jones, an ex-companion of the Doctor was tasked with alerting him about it when the preparations for the invasion were discovered. Apparently, now-Sir Alistair Lethbridge-Stewart still had some involvement with UNIT at this time, though he had gone to Peru for undisclosed reasons.
Following the defeat of the Sontarans, UNIT began reverse-engineering some technology scavenged from the aliens, and launched Project Indigo to create a backpack-sized teleportation device. Jones was seconded as medical advisor for the project (which was top secret, although Harkness found out about it), and stationed at UNIT's base in New York City. UNIT also developed a contingency plan called the Osterhagen Project; in the event of global conquest that seemed unending, three out of five UN facilities would end humanity's suffering by destroying the planet with nuclear weaponry under Earth's crust.
Following the relocation of the Earth and two-dozen other planets to the Medusa Cascade, UNIT went on high alert, and then to a war footing as the Dalek invasion began. Both the Valiant and the New York headquarters were overrun by Daleks and apparently destroyed, and the United Nations surrendered soon after. Martha Jones, however, escaped using the Project Indigo device, maintaining possession of an Osterhagen key in the process. She used Project Indigo to reach the Osterhagen Station in Germany. The Chinese and Liberian stations had been already activated. She was teleported away by the Daleks themselves before the bombs could be triggered. The Doctor later asked her to have the Project dismantled.
During Easter 2009 UNIT was called out to a tunnel near Brixton after a bus carrying the Doctor and other passengers had gone through a wormhole. The Doctor managed to contact UNIT and he got through to the senior officer of site Captain Erisa Magambo and also spoke with their scientific adviser Professor Malcolm Taylor. The Doctor manged to get the bus back to its current location but the Swarm managed to get through to Earth. Magambo and UNIT fought the stingrays, which resulted in UNIT winning and she later thanked the Doctor. The Doctor also recommended to Magambo that there might be two more potential UNIT recruits from the bus, namely Barclay and Nathan.
When the Master turned every Human into a copy of him on Christmas Day 2009, UNIT became under his command.
Beyond the 21st centuryEdit
Some time in the future, following Human expansion into the galaxy, UNIT had evolved into the Foreign Hazard Duty.
By the 26th century, UNIT has become a secret society called the Unitatus. Unitatus survived at least until the 30th century
In the early 1970s, UNIT was overseen by a Commander-in-Chief in Geneva.
UNIT's status was supported by enabling legislation that allows it to assume emergency powers when necessary. Although it operated under the authority of the United Nations, its members are seconded from the host country's military and are still bound to obey that chain of command. Lethbridge-Stewart, for example, reported to the Ministry of Defence and the Prime Minister. However, where such orders conflict, appeals could be made to Geneva.
Due to the international nature of the organisation, it was sometimes viewed with suspicion by local military and national security agencies, who felt that it might impinge on their sovereignty. UNIT's existence was known to the public, but mainly as a security organisation; its actual agenda was classified, some believing it to be some kind of covert counter-terrorist unit.
Despite the change of name to the Unified Intelligence Taskforce, the United Nations commands and funds UNIT.