An ancient, highly advanced civilization that mastered the technique of dimensional transport across
interstellar distances. The Iconians, referred to in ancient texts as "Demons of Air and Darkness," were all believed destroyed 200,000
years ago by orbital bombardment that devastated the surface of their planet. It has been speculated that the Iconians did not all perish in
the attacks, but rather used their gateway technology to escape to other nearby planets. The similarity between the Iconian language and
Dewan, Iccobar, and Dinasian has been cited as evidence to support this theory.
TNG "Contagion" ; Star Trek Encyclopedia II
The Homeworld is Iconia.