Hardcore fans already know this, but Transformers weren't always Transformers.
The biggest animated series of the 80s was actually cobbled together following a 1983 partnership between Hasbro and Japanese toy company Takara, who had already released some transforming toys -- many of who you might recognise -- called Diaclones and Microman.
The deal meant Hasbro bought the rights to a bunch of existing figures and designs used in Takara's older toy lines. These would be smashed together and have a new story written around them, which would become what we now know as Transformers. Autobots vs Decepticons, More Than Meets The Eye, all that stuff. In return, Takara got the rights to distribute the new Transformers toys in Japan.
This is why, as you'll see in this collection of amazing old Japanese commercials (made using footage from Takara's own archives), there are so many characters we'd eventually come to know and love as Transformers driving around as, well, not Transformers.
The Jazz intro at 0:45 is particularly rad.
If you ever wondered why the oldest Transformers had some weird quirks -- like Optimus Prime's trailer containing a cockpit for a human gunner -- this is why. He wasn't originally designed as the Autobot leader, he was just a transforming truck with a human pilot. It's only when Hasbro and the show's writers got involved that he became a gruff old dude with a catchy slogan.
The Diaclones are probably the more famous/important of the two series that eventually became Transformers, and date back as far as 1980 (though the transforming vehicles didn't show up until 1982). Everything from the larger, original Autobot cars to the Decepticon jets to the Dinobots were originally Diaclones.
Microman, on the other hand, was a line where the toys were supposed to transform into an object that was close to 1:1 scale. Megatron, Soundwave and Perceptor all came from the Microman line, but so too did all the smaller Autobot cars (like Bumblebee and Cliffjumper), as they'd originally been designed to transform not into real cars, but toy ones.
Nearly every Transformer seen on the TV show between its debut and the release of the 1986 animated movie was originally designed as a Diaclone or Microman toy in Japan. It's only when the film, which skips ahead decades and starts introducing futuristic vehicles, that Hasbro were able to start introducing characters of their own design.
Which says a lot about people's feelings towards the series as a whole! Not many folks will list post-movie Transformers as their favourites, and I think a lot of that has to do not with the characters, but their robot/vehicle designs. What made the original Transformers so cool was the fact they were real vehicles. Car transporters, family vans, actual military jets.
The later Transformers like Rodimus Prime and Galvatron didn't have this link to the real world (or a child's fascination with the huge objects around them), so if your favourite Transformers were all original ones, remember to save a little thanks for the Japanese toy lines that originally designed them.
Diaclone logo courtesy of TFwiki.