Seeking a means to locate the young runaway mutant Scott Summers, Charles Xavier (Professor X) built a makeshift device he dubbed Cyberno. Pinpointing Summers’ location, Cyberno also detected a second mutant, the criminal Living Diamond. After rescuing Summers from the Living Diamond and recruiting him as Cyclops, the first member of the team of trainee mutants that became the X-Men, Xavier realized that an enhanced version of Cyberno would allow him to locate even more mutants. Refining the design, Xavier created a new version shortly before Jean Grey joined the X-Men as Marvel Girl, naming it Cerebro, from the Latin “cerebrum”, meaning “the brain.” The original Cerebro was simply a control panel built into Xavier’s desk, to which Xavier later connected a radar-image beam that projected images of the mutants it detected as well as a multi-frequency booster enabling Cerebro to pinpoint mutant locations which was connected using plastisthene tubing, an ultra-magnetic splicer and super-tensile cables. More additions followed, including a tape recorder, visi-screen, a memory-erasing helmet, and an emergency circuit that would automatically activate Cerebro upon detecting a mutant signal.

Cerebro soon grew to require a dedicated chamber within the mansion. Realizing the danger inherent in a subversive force gaining control of the device, Xavier installed numerous security protocols to help safeguard Cerebro. Xavier continued to upgrade the machine, even creating small portable versions that could pinpoint an individual mutant’s location via telemetric communication with the parent unit. Following the X-Men mansion’s destruction by the alien Sidri, it was rebuilt and its technological systems, including Cerebro, were upgraded with alien Shi'ar technology. The new Cerebro consisted of a powerful computer core, specialized wave-sensing components, and an interface helmet that could amplify its user’s telepathic abilities. A second unit was subsequently installed at the Muir Island Research Center, run by Xavier’s trusted friend Moira MacTaggert.

After the techno-organic alien Phalanx infiltrated the mansion and sought to access Cerebro’s files, the X-Man Banshee was forced to initiate Cerebro’s self-destruct sequence. Months later, Xavier finished rebuilding Cerebro; however, the computer detected a massive energy spike in northern New Jersey (caused by several mutants going wild on a train) immediately after initializing, and overloaded. The X-Man Bishop was then tasked with repairing Cerebro, noting that the advanced technology used in its design was the same as that in his own future time. When the X-Men were attacked by the government-sponsored Operation: Zero Tolerance anti-mutant taskforce, its leader, Bastion, confiscated the mansion’s entire contents, including Cerebro. Bastion’s Prime Sentinels attempted to interface with Cerebro, whereupon its security protocols engaged, downloading its central programming into the Prime Sentinels’ neural network. Combined with Bastion’s nanotechnology, Cerebro achieved sentience as Cerebro Prime.

Creating a nanotech body for itself, Cerebro set out to realize Xavier’s dream through the ultimate fulfillment of its own program to find, catalogue, and store mutants. First, it had to overcome Bastion's nanotech programming, so it shaped itself into a facsimile of Xavier called “The Founder” and generated nanotech X-Men based on amalgams of its records. The Grey King (Addison Falk) was a power-dampening telepathic and telekinetic mutant based on Cyclops and Jean Grey; Rapture (Sister Joy) was a blue-skinned winged mutant combination of Archangel and Mystique; Chaos (Daniel Dash) was an autistic mutant who could generate cosmic energy similar to Havok; Landslide (Lee Broder) was a massive, super-strong and agile mutant that resembled an amalgam of the Blob and the Beast; Crux (Cristal Lemieux) was a teenage French mutant with the ability to manipulate temperature extremes akin to Iceman and Sunfire; while Mercury possessed a liquid metal body with razor-sharp claws in resemblance of Colossus and Wolverine.

These faux X-Men kidnapped Shadowcat, as Cerebro knew of her exceptional computer skills and believed she possessed the ability to save it. Thinking that Cerebro was the real Professor X, Kitty agreed to help. Cerebro and its X-Men then attempted to use a mutant-tracking satellite to catalogue all the mutants on the planet, but were stopped by the true X-Men. The rocket and the satellite were both destroyed, and the Founder abandoned its pretense of being Xavier. It reabsorbed the faux X-Men, then sought out Xavier, finding him at two locations simultaneously. To that end, Cerebro created two Cerebrite extensions of itself. One traveled to San Francisco where it faced a powerless Xavier alongside the Blob’s Brotherhood of Mutants, while the other traveled to Tajikinistan and found the Mannite Nina, who had imprinted Xavier’s psi-pattern, and her guardian Renee Majcomb. Tracking Cerebro to its base in Florida, the X-Men were easily defeated. Finally, Xavier had Nina restore his powers, and using them in conjuction with her own, accessed Cerebro’s nanotech mind and expanded its “consciousness” to the entire world. Cerebro’s nanites, which it was planning to use to control all humans on the planet, were stopped and destroyed. Cerebro was overwhelmed by the unique individuality of each person and overloaded, expiring in its creator’s arms.

Convinced that Cerebro was still a necessity, Xavier subsequently built a new version. Soon after, its files were accessed by X-51, the Machine Man, who was seeking a way to prevent his CPU from being corrupted by Sentinel programming. Cerebro was later significantly upgraded to consist of a large spherical chamber with a suspended walkway leading to the control console, command chair and interface helmet in the center. Recently, the Beast adapted Xavier’s original designs and built a more powerful version, which he dubbed “Cerebra.”