L'Deus was a Romulan statesman that lived during the early years of his race's development on the planet Romulus.

During the time when the planet was divided into numerous city states with wars being fought against one another, it was L'Deus that advocated the unification of the states into a single entity during the chaotic arguments that erupted in the assembly. He would depart into the night after this and ultimately successful in uniting the states into a single nation with the signing of the D'Vatta.

Hologams of him exist in the museums of Portora and a statue of him holding the D'Vatta while pointing to the stars exists in D'Sivas. An inscription on the statue has the following words which he spoke during his time:

"We must join together or fail. We cannot reach our home, our destiny, by fighting among ourselves. We are one. We must be one. Let us act as one. To act any other way is to deny our children their right to the stars that are theirs." (FASA RPG module: The Romulans)

The FASA material states that he was the first Emperor of the Romulan people which contradicts The Way of D'era: The Romulan Star Empire material which states that Valkis was the first Emperor of the Romulan Star Empire.