This might come as no surprise, but the Transformers share their nation of origin with almost all other giant robots. Like Gundam, Macross, Mazinger and the Power Rangers, they were once the crazy imaginings of toy designers in good old Japan.
Before they were rebranded Toransufōmā by Takara, everyone’s favourite transforming robots were previously toys named Diaclone and Microman. Sorry, we mean Daiakuron and Mikuroman. Hasbro - the same company that makes G.I. Joe and My Little Pony - combined and rebranded the two toylines into the Transformers - while developing a backstory for the new transforming toys that resulted in the canon of the two warring factions of robots we know today.
The Japanese versions of the Transformers had their own cartoons to support their versions of the toys, with hilarious series names like Super God Master Force and Fight! Super Robot Life-Form Transformers and with even more ludicrous terms like Autobot Godmaster and Emperor of Destruction Deathsaurus. Their cartoons evolved separately from the American version, which spawned a whole line of characters and toys exclusive to Japan, such as Star Saber and Victory Leo (snort).