Kurn was a Klingon warrior, the son of Mogh and younger brother to Worf. His true family name was kept secret until 2366, when Mogh was accused of being a traitor. Kurn later supported Gowron during the Klingon Civil War, and, afterward, gained a seat on the Klingon High Council. However, he fell from grace when Worf refused to support the Klingon invasion of Cardassia. To regain his honor, his memory was wiped and he assumed a new identity.
Kurn was not a year old when his father Mogh left Qo'noS for Khitomer with his wife and older son Worf. However, because Kurn was so young, he was left in the care of Lorgh, a family friend. After his family was presumed killed at the Khitomer Massacre, Lorgh accepted Kurn as his own son. Kurn did not know his true family until he reached the Age of Ascension. Kurn eventually joined the Klingon Defense Forces and rose to the rank of commander.