Kaien Rijin is a historical character from Final Fantasy XIV. He was the last king of Doma before it fell under the Garlean Empire's control. His son, the crowned prince Hien, is the main character of the Final Fantasy XIV: Stormblood main scenario, fighting to liberate the lands.
Kaien is said to be one of the greatest swordsmen. However, he lost to Zenos yae Galvus.
Behind the scenes
Kaien, if written with the kanji 海燕, means "sea swallow". This name goes along with his son's name, Hien (meaning "flying swallow").