The Transformers (or Cybertronians) are the main species of the planet Cybertron and its colony worlds.
Cybertronian mythology held the belief that the species was created by Primus. Their early society was governed by the Knights of Cybertron before they left Cybertron and the Thirteen Primes took power. The Thirteen splintered however and the planet became consumed by a planet-wide civil war which ended ten million year prior to the present day. During this time, the ancient Titans departed Cybertron to establish new outposts of Cybertronian civilization with the intent of founding a galactic empire. Despite the colonies being founded however, the plan fell through for reasons unknown. Peace reigned following the war until the second war, the Great War, broke out four million years ago.
The war rendered Cybertron lifeless forcing both Autobots and Decepticons to leave their home and continue their battles on other planets. As a result of Cybertron having perfected interstellar travel, galactic powers, such as the Solstar Order, presumed that all Cybertronians were a unified race committed to destroying organic civilizations. When the Autobot/Decepticon war spilled over into the Solstar/Wraith war, it was discovered that in spite of the inorganic physiology of the Cybertronians, they were susceptible to possession by the Wraiths which resulted in unstable yet extremely powerful fusions. The vast majority of Wraiths however were disgusted by the mechanical physiology of the Cybertronians and swore off merging with them.
In the mid to late 20th century, the Cybertronians began landing en masse on Earth. The repeated incursions onto the planet as well as the collateral damage that was caused convinced Joe Colton that the Cybertronians would one day destroy Earth.
In 2012, Optimus Prime managed to reignite Cybertron's core, reuniting the scattered race before they contacted their long lost colonies, forming the Council of Worlds. After the Decepticon tyrant Galvatron nearly conquered the Earth, Optimus annexed the planet into the Council of Worlds.
The Prysmosian Garrison Kreiger, who already viewed technology as a contemptible imitation, deemed the Transformers as unholy abominations. Forming the Iron Ring, Joe Colton led a genocidal campaign against the Transformers before his plan was hijacked by Kreiger who revealed himself as Merklynn and terraformed a portion of Cybertron's underground into New Prysmos.
The Prysmosians refugees who came to inhabit New Prysmos chafed under the Cybertronian regulations however and supported Virulina's declaration of a genocidal war after it was discovered that Prysmosian magic induced necrotic symptoms in Cybertronians. Though the Talisman came close to ending all native life on Cybertron, Wheeljack's anti-Talisman bomb, combined with Galadria's healing spell managed to neuter the Talisman and leave Cybertron in the hands of its people, minus a small patch of land for New Prysmos.
- Technically "Cybertronian" refers to a native inhabitant of Cybertron. "Transformer" is the catch-all term for any inhabitant of the Council of Worlds.