This timeline is pieced together from what began as the official X-COM timeline from the X-COM Interceptor manual, and was later brought up to date by the talented Shaun Green to include the events of the Fourth Alien War as detailed in X-COM Apocalypse.

Please note that if you're wondering why X-COM Enforcer is not mentioned in this timeline, it's because it was a top secret mission and not part of public knowledge even after most of the documented events of the First Alien War were released.

The long history of the Extraterrestrial Combat Unit (X-COM) stretches over more than a century - a century of bitter, drawn-out war of attrition with the alien invaders. The story begins in the late 1940's, in the area of New Mexico known as the Nevada Desert...


First Encounter


The 509th Bomb Group regiment of the Army Air Corps were the first to officially report the crash of a "flying disk" in the desert near Roswell, deep within New Mexico. The original report explained that of the three occupants of what was termed a "UFO" (Unidentified Flying Object), one had survived the crash. Two had died. Before daybreak, however, government agencies had rapidly acted to retract this version of events, instead claiming that the "UFO" was in fact a weather balloon.


For the last fifty years, men and women (many of them American in nationality) have claimed to have been abducted by alien lifeforms. Many claim to have been abused, or impregnated, or tested upon, or questioned. Most of the world chose to ignore these "crackpots", focusing instead upon the more mundane everyday events that plague us all. However, on the fiftieth anniversary of the Roswell incident, UFO sightings across the world skyrocket. Whilst this is at first believed to be caused by tabloid hype of the anniversary, soon intellectuals, officials and the legitimate press join the ranks of "the believers". One of the most popular headlines at this time is "We Are Not Alone". Whilst this has been claimed and theorised by many, it has never been proved. Until, it seems, now.


Credible reports of human abductions steadily filter into government files and the press. These abductions all follow a similar pattern - the victims inhabited rural areas with a low population density. The governments of the world, worrying at what this might really mean, begin to bring their armed forces to a state of full combat readiness. Contact is attempted, but no results are forthcoming. As the abductions continue, military action is considered to defend the peoples of the world. Japan, taking the lead with it's stereotypical blind bravery and courage, forms the 'Kiryu-Kai' - the first anti-alien combat force. They are equipped with the very latest Japanese military equipment, and are manned by the country's finest, but after five months they are forced to disband, without downing a single UFO.

The United Nations was the next to take action. On the 11th of December, 1998, the Security Council gathered in Geneva to decide upon a course of action. It is eventually decided by the representatives of the world's nations that the only way to combat the aliens is to present a united front. Together, they agree to form a covert, multi-national military-based unit to investigate the alien threat and gauge it's depth. This organisation is known as X-INV. After just a few months, however, the aliens are finally decreed to be hostile, and are recognised as such by the new Council of Funding Nations. X-INV becomes X-COM - the Extraterrestrial Combat Unit.

X-COM is assembled from the finest soldiers, pilots, engineers, scientists and intelligence operatives from across the world. Together with the very latest military equipment, it is hoped that this will be capable of defeating the alien menace.