Delenn of the Family of Mir was an aide to Grey Council leader Dukhat and subsequently sworn in to the Grey Council herself just prior to the outbreak of the Earth-Minbari War (Atonement, In the Beginning).  It was her decision, in a moment of anger, that led to the Minbari slaughter of the humans, about which she still feels guilty (And the Sky Full of Stars, And Now For a Word, Ceremonies of Light and Dark).

She acted as Ambassador to Babylon 5 mainly to watch over Commander Sinclair should he recall his encounter with the Grey Council during the Battle of the Line (And the Sky Full of Stars).  She attempted to stage a Minbari rebirth ceremony aboard the station on two occasions, and it was disrupted both times (The Parliament of Dreams, Ceremonies of Light and Dark).   She was offered leadership of the Grey Council but refused (Babylon Squared), determined instead to follow prophecy and transform herself into near human form (Chrysalis, Revelations), later coming to terms with the consequences of being a half-human female (Soul Mates).  Her aide on Babylon 5 is Lennier, who is also her secret admirer (Ceremonies of Light and Dark).

After her removal from the Grey Council (All Alone in the Night), leaving it unbalanced with four Warrior Caste Members and only two Religious, along with their defiance of realizing prophecy to commit themselves to fighting the Shadow War, she disbanded it (Severed Dreams).   She suffered a brutal interrogation before the Vorlons seemed happy with her presence and position to fight in the upcoming Shadow War (Comes the Inquisitor).

After Sinclair was sent back in time, she was appointed as the new Ranger One, a position disputed by her Warrior Caste rival Neroon (Grey 17 is Missing). Through developing a relationship with Captain Sheridan (A Race Through Dark Places, Confessions and Lamentations, Sic Transit Vir), she eventually got engaged to him (Falling Toward Apotheosis) and embarked on undergoing several Minbari courtship rituals with him (Shadow Dancing).

When it came her time to face the Dreaming, a Minbari ritual to determine her suitability to pursue her relationship with Sheridan, she learned Dukhat's dying words to her: that she was a "child of Valen", descended from Sinclair and therefore in possession of human DNA (Atonement). To conceal this information from becoming widely known, she was allowed to continue the relationship as a "peace offering" to the humans after the War.

She finally reformed the Grey Council, with a majority of Worker Caste members to maintain control, to stop the Religious-Warrior Caste conflicts (Rumours, Bargains and Lies, Moments of Transition).   She assisted in the final attack against President Clark's forces on Earth (Endgame) before forging the new Alliance and marrying Sheridan (Rising Star).

In late 2262, she fell pregnant (Wheel of Fire), with a son, David (War Without End, Part II, Sleeping in Light).  She lives for at least another 100 years (The Deconstruction of Falling Stars).

Played by Mira Furlan, a Yugoslavian actress.