Kosh is a fictional character in the universe of the science fiction television series Babylon 5.
Kosh Naranek
Kosh Naranek (it has been noted that Naranek may be a title, not part of a name) is the Vorlon ambassador to Babylon 5 from 2257 till his death 2260 (or 2261, to be technical).
Kosh was killed (mostly) by Shadows in 2260, after involving the Vorlons in the Shadow War. Kosh "broke" a piece of himself off mentally and stayed within John Sheridan, a fact not revealed completely until Sheridan's own death and resurrection in late 2260/early 2261.
The last remainder of Kosh died while fighting Kosh II Ulkesh with Lorien and Lyta Alexander.
Kosh II (Ulkesh)
Never mentioned in the series itself, the name Ulkesh comes from a canon Babylon 5 novel, To Dream in the City of Sorrows.
Ulkesh was the successor of Kosh I on the station following Kosh I's death at the hands of the Shadows. Contemptuous and arrogant, he became a liability when the Vorlons decided to continuously intercede in the Shadow War. Unwilling to leave the station when hostilities by the Vorlons threatened friendly planets, Kosh II was killed by a combined attack from Lorien, Lyta Alexander and the psychic remnants of Kosh I.
