Gorn King was the title given to the leader of the Gorn Hegemony in the 23rd and 24th centuries.
History[]
In the 23rd century, it was ruled by a King of the Gorn Hegemony, an old head of state who delegated his authority to several vassals who became at odds with one another for supremacy of the Hegemony. The king himself was sheltered from these political problems by those loyal to him. This led to degradation within the Gorn government. It was believed that, without a strong leader, the Hegemony might eventually collapse and fall into civil war. (TOS video game: Klingon Academy)
In the 2380s, the leader of Gorn was known as the Imperator of the Gorn Hegemony. (ST - Destiny novel: Mere Mortals)
Star Trek Online[]
In an alternate timeline, Xrathis held the position of King of the Gorn in the year 2384, and after a vessel of the Hegemony attacked a Klingon ship, he claimed that the Gorn crew were rogues. Despite this being the case, he refused to hand over any Klingon Defense Force survivors back to the Klingon Empire. This decision led to Chancellor Martok expelling the Gorn diplomats from the Klingon Empire.
In 2387, Xrathis died of old age and was succeeded by Crown Prince Slathis. As of 2409, Slathis was Gorn King and held a non-voting seat on the Klingon High Council. (ST website : The Path to 2409, STO novel: The Needs of the Many)