The Governor-General of Krant was a political office in the Hydran Kingdom. As with other Governors-General, the Governor-General of Krant was the representative of the King on a planet, and whose approval was necessary for all planet-specific laws with a planet-wide scope to actually become law. Holders of the office typically hold the rank of duke.
Kayachey was in office in 2415. At that time, Krant was a major transit point for Unity Three Starbase and Krant was used for a diplomatic mission. (Star Trek: False Vacuum: "Wagon Train to the Stars")