G'Kar served as the Narn ambassador to Babylon 5 for about five years, starting when the station opened in 2258. While Narn was occupied by the Centauri, G'Kar remained on the station as a political refugee. He continued to represent Narn to the Interstellar Alliance after its foundation, refusing to accept an executive role in the post-war Narn government. He died in 2278, mutually strangling Londo Mollari.
Like all Narns, G'Kar appears to be somewhat stronger and substantially tougher than a human. At some point before he was stationed on Babylon 5, G'Kar had "gills" surgically implanted in his neck that allow him to breathe normally in toxic atmospheres; the limits of these "gills" are undefined.