Ivar was born in a family of shamans that worshiped and served Maxwell from generation to generation.  When Maxwell descended in Nia Khera, it was decided that Ivar would be her personal servant.  From a very young age, he was aware of the expectations people had for him and realized how “special” he was. He took a lot of pride in his role, which became his reason of existence. 
His tasks include assisting Milla, attending to her and her shrine, as well as protecting the village.
When Milla decided to take Jude on her journey instead of him, his pride was badly hurt. He considered Jude unworthy because, to him, he did not seem to take the role of handmaid seriously. He blamed him for all the misfortune that happened to Milla. Little by little, his desire to surpass Jude replaced his wish to accompany Milla on her journey. As a result, he failed to realize the trust Milla put in him when she entrusted him the key and instead prioritized his rivalry with Jude. He was easily deceived by Alvin and defied Milla’s orders to stay in Nia Khera. However, despite the terrible consequences of his action, all he thought about was Jude. 
When Milla died and Musee attacked Nia Khera, he realized that he had failed his two most important missions - protecting Milla and the village. He tried to take his grief out on Jude by challenging him, but could not defeat him. Instead, Jude told him that neither of them were special. That made Ivar realize that Jude was aware of his own weaknesses and limitations and yet kept going forward - that he was much more mature than he was. However, he would not acknowledge this aloud and instead chose to flee, leaving Nia Khera behind.