The Transformers franchise started sometime around early 1983.  Takara began selling some of their popular Japanese robot toy lines in the United States, including marketing Diaclone under the name Diakron and parts of their new Microman under the name Kronoform.  Shortly afterwards, Takara and Hasbro representatives met at the 1983 annual Toy Fair® (owned and managed by the Toy Industry Association™) trade show in New York.  Takara was trying to find US-based partners to help them sell their brands, and soon struck a licensing deal with Hasbro.  The two companies already had some business history together.  Meanwhile, Tonka Corp. of Minnetonka, Minn., had a head start by introducing a competing toy line, GoBots, in early 1984. 

"Although Transformers appeared five months after GoBots, Hasbro came from behind and outsold GoBots almost 2-1," according to the book, "TOYLAND: THE HIGH STAKES GAME OF THE TOY INDUSTRY."   

Once the deal was struck with Hasbro, Takara naturally stopped marketing the toys on their own, hence the rather short-lived lifetime of those lines in America.  Hasbro, for whatever reason, felt they needed to develop a new story for the toys rather than sticking with the established stories from Takara, so they approached Marvel for help (Marvel had previously done development work on the 80's G.I. Joe franchise for Hasbro, to great success.)  The backstory and characters were created by Marvel, and of course Marvel also released the Transformers comic series.  Marvel Productions -- their animation branch -- did the cartoon series under contract from Sunbow ... so in a nutshell, that is how The Transformers franchise started and the rest is history in the making! 

Please take the time to indicate that this was a helpful guide, if you thought it was so, by clicking "Yes" below.

Thank you for your time, best of luck and God bless to all.