In 2255, Lieutenant James T. Kirk led his first planetary survey mission to Neural, and became a good friend of Tyree. Kirk returned to the planet in 2268 as Captain of USS Enterprise, and found Tyree had risen to become leader of the Hill People – married to a Kahn-ut-tu witch-woman named Nona.
Tyree saw his way of life abruptly change after Klingon agents began supplying firearms to Neural's village dwellers. He was a man of peace, and resisted his wife's suggestions to obtain weapons to fight the village dwellers. His wife, Nona, cured Kirk from the bite of a mugato, an animal whose bite was poisonous and always deadly. Tyree became jealous of the bond that developed between Kirk and his wife. Tyree became enraged after his wife was killed by the villagers, and asked Kirk to supply his people with guns like his enemy had. Kirk, hoping to even the odds and give the Hill People a fighting chance, supplied Tyree's men with comparable weapons. (TOS: "A Private Little War")