The Ship-Kings were 5 kings(not 4) of Gondor in a line unbroken. It was started by Tarannon Falastur, who started building ships. Hyarmendacil extended his realm by securing Umbar and defeating the Haradrim. His nephew then claimed the throne, and his son Atanatar ran to the Northern Kingdom's remnant of Cardolan. His nephew Meanyarion then invaded Bellâkar, a southern Black Numenorean state, and conquered it. Meanyarion then took the name Hyarnusdacil.