This trope has been well known recently in the animated series Rick & Morty which depicts a mega-space habitat populated by millions of Ricks ruled by a Council.
I don't know of many precedents for this idea. From what I recall, there is a very similar situation in several issues of Jonathan Hickamn's version of Marvel's Fantastic Four comic from about 2009, where Reed Richards, arguably the smartest human in the Marvel Comics Universe encounters a large organization of Reeds from alternate Universes.
When and where, in comics or television, film or F&SF literature, was this idea first published?