DiWahn was a class M world located near Federation space, in orbit of a yellow star. Prior to the bombardment of the Iconian homeworld approximately 200,000 years ago, there was an Iconian outpost present on the planet. When the Iconian homeworld was attacked, along with Ikkabar and Dynassia, DiWahn was one of the three worlds that the surviving Iconians escaped to via an Iconian Gateway.

The Iconian survivors, who became known as the DiWahn, were able to successfully adapt the planet for settlement. Over the centuries, however, the survivors split into a number of competing fiefdoms. During this time, the Order of the Faithful, or the unDiWahn safeguarded the Iconian knowledge brought to the world by the original colonists, and awaited the return of the Devil's Heart so that they could ensure that the stone's mission could continue. (TNG novel: The Devil's Heart)

The DiWahn developed their own distinct language, based on the original Iconian mother tongue. In 2365, Lieutenant Commander Data was able to use the DiWahn language, plus the languages developed on Ikkabar and Dynassia to help reconstruct the Iconian language. (TNG episode: "Contagion")