Esbern is a Nord and one of the last remaining Blades, along with Delphine in The Elder Scrolls V: Skyrim. He is a wise conjurer and knight that can act as the seer for the Blades after their revival. He plays a major role within the main questline. He is voiced by Swedish actor Max von Sydow.
Esbern is a kind, strong man. He serves as Dragonborn's close friend and mentor throughout the game.
He is initially in hiding from the Thalmor tracking him down and murdering him, but when they got word of his hiding place, Delphine sent the Dovahkiin to track him down and bring him to her before the Thalmor reached his location.
After the last of the Blades regroup, they head for Sky Haven Temple and discover an Akaviri carving called Alduin's Wall, depicting how the Dragonborn can defeat the World-Eater.
During this time, Esbern and Delphine send the Dragonborn to recruit new members into the blades in an attempt to survive the group of dragon slayers. He also acts as the Dragonborn's main advisor.
After holding a peace conference with the Graybeards, Esbern comes to the realization that their leader is Paarthurnax. He instructs the Dragonborn to kill him for the actions he caused in his past, back when he was a follower of Alduin. Unless the Dragonborn slays the ancient gold dragon, he and the blades will not provide anymore services.