I am Ser Alberic Bale, knight of Ishgard. The Holy See is much obliged to you for your aid.
Alberic Bale, as the former Azure Dragoon, trained Estinien as a dragoon, who soon succeeded him. However, when the latter betrayed the Holy See by stealing the Eye of Nidhogg, Alberic was forced to request aid from the Lancer's Guild in Gridania, leading to the Adventurer being enlisted to aid him. Upon learning the Adventurer was seemingly chosen by the Eye as a second Azure Dragoon, Alberic presented his soul stone and trains them in the way of the dragoon.
During the Adventurer's trainiong, Ser Alberic relates how the Eye was originally taken by Haldrath during the founding of Ishgard, prized out of the great wyrm's eye socket. Since then, Nidhogg had unleashed his wrath on the Holy See seven more times throughout its history. The most recent happened twenty years ago, when Ser Alberic was Azure Dragoon. Nidhogg's rampage only ended near a village called Ferndale, where he engaged the great wyrm in battle for three consecutive days where it was driven off for good. The only survivor of the village was Estinien, whom Alberic took in and trained.
In the quest "Double Dragoon," Estinien suddenly reaches out and asks to parley. At Boulder Downs, he reveals Nidhogg has already awakened, and only took the Eye in hopes of drawing his wrath away from the Holy See. He believes that since two Azure Dragoons were chosen, they should join forces and confront the wyrmking. He asks the Adventurer acquire drachen mail and finish their training, and Alberic instructs on how to pursue these tasks.
Upon completing them, he confesses the truth of what happened at Ferndale. He reveals that as he drove his spear into Nidhogg's empty eye socket, he met the wyrm's gaze and became overwhelmed with the dragon's emotions. Fearing he would be enthralled under this torrent, he relinquished the power of the dragoon, and used the ensuing clarity to rout the great wyrm. Unfortunately, Nidhogg's fellow dragons took the occasion to finish the job, razing the village to the ground. Alberic could only save one child - Estinien - from the slaughter. He expresses his intent to confess the truth when they next meet Estinien.
In the quest "Into the Dragon's Maw," Estinien sends word that Nidhogg is about to make a move and requests a rendezvous at Steel Vigil. There, he turned his spear towards his former master, and revealed that the Eye told him the truth of Ser Alberic's actions twenty years ago, and that he kept the loss of the Eye from the archbishop. Denouncing him as a coward, Estinien declared his intent to slay Alberic and then take out the Great Wyrm himself. As Ser Alberic earned that his emotions leave him dangerously vulnerable to the dragon's influence, the Adventurer engaged the Azure Dragoon in battle. As Estinien began to lose the duel, the voice of Nidhogg began to offer power. As Estinient reached out to receive it, a blinding flash occured before he and the wyrmking's aura vanished.
Ser Alberic explains that he saw what appeared to be the image of Haldrath the Dragonseye in the Adventurer's place as the wyrmking was banished. Amazed, he realized the adventure had awakened the power of the first Azure Dragoon, which manifested in the original Drachen Mail of the first Azure Dragoon. With Nidhogg's aura fading and the dragons quieting down, Ser Alberic hopes that Estinien is still out there.