A Dohlman was the ruler of Elas, homeworld of the Elasian race.
The Dohlman was a monarchic role over a tribal society and a semi-feudal political structure. The position was directly served by a number of regional overlords and important local warlords, who elected a new Dohlman from their own ranks. A Dohlman ruled for life. (Decipher RPG module: Worlds)
An important body of these lords below the Dohlman was the Council of Nobles. (TOS episode: "Elaan of Troyius")
In the mid-23rd century, the current Dohlman was Elaan, though she abdicated in 2268 to marry the ruler of Troyius (TOS episode: "Elaan of Troyius"), becoming the first and, to date, only Dohlman to vacate from the position before death. The two then ruled both of their worlds jointly , while Elaan's nephew, Dokkun, succeeded her as Dohlman of Elas. (Decipher RPG module: Worlds; FASA RPG module: The Orions: Book of Common Knowledge)
The Dohlman's palace was located in the capital city of Ekeos, and was once the palace of the kings of Ekeos. It was known for its luscious garden courtyards, brightly colored decorations, and impressive stone columns that resembled those of Classical Greece. It was expanded and refurbished multiple times. (Decipher RPG module: Worlds)