Who is al'Lan Mandragoran from The Eye of the World and what is their importance?

Lan is Moiraine's Warder, her companion and personal bodyguard. He is always near her, watching over her. Lan is the first to raise the alarm when Emond's Field is attacked by Trollocs, able to sense the creatures when they are close by. He helps to fight them off, and then helps Moiraine lead the group across the land. He instructs the boys on how to use their weapons, and he plays the roles of scout and night watch, rarely resting. Lan is impressed with Nynaeve's tracking skills and her spirit. An attraction grows between them, but when he and Nynaeve speak of it in the Blight, he can't act on his feelings, unwilling to make Nynaeve a widow with his certainty that he will die in the line of duty. In the Borderlands, Lan is known as an uncrowned king, ordained as the last king of Malkier when he was a child before the land was lost to the Blight.