Over a hundred years before the events of Fire Emblem: Genealogy of the Holy War, Jugdral was ruled by the tyrannical Loptrian Empire, which committed a great number of atrocities. Ullr was one of the revolutionaries who rose up in rebellion against the Loptr Empire. However, the forces of the rebellion were no match for the might of the Empire. With their numbers greatly diminished, the remaining 12 revolutionaries had no choice but to barricade themselves inside the Tower of Dahna, preparing for their final battle. They were in luck, however, as twelve dragon gods intervened, granting each of them divine power through a blood rite. Through this ritual, Ullr gained increased combat prowess and the ability to use the sacred bow Yewfelle. This event came to be known as the Miracle of Dahna.
With their newfound boons from the dragon gods, Ullr and the other revolutionaries successfully overthrew the Loptr Empire. Ullr's skill in battle led to her becoming known as the Bowmaster, and the revolutionaries became known collectively as the Twelve Crusaders.
Following the fall of the Loptr Empire, the Crusaders founded their own nations. Ullr established the dukedom of Yngvi. Yngvi, along with dukedoms founded by fellow Crusaders Baldr, Fjalar, Bragi, Nál, and Thrud, made up the kingdom of Grannvale, which itself was founded by the Crusader Heim.
- The Bowmaster.
- One of the 12 crusaders who gathered at the Tower of Dahna. With her holy bow Yewfelle, she has felled many a foe. Appears in Fire Emblem: Genealogy of the Holy War.
| Holy Yewfelle|
|A||Life and Death 1||-||-|
|Life and Death 2||Life and Death 1||-|
|Life and Death 3||Life and Death 2||-|
|Life and Death 4||Life and Death 3|
|C||Time's Pulse 1||-||-|
|Time's Pulse 2||Time's Pulse 1||-|
|Time's Pulse 3||Time's Pulse 2|
Subjective: The following part of this article is based upon the editor's personal experiences and opinions, and therefore may not be applicable for all readers.
- Prior to her debut in Fire Emblem Heroes, Ullr's gender was unknown.
- Ullr is the first of the Twelve Crusaders to become a playable unit in Heroes.
- Ullr is the third non-Heroes original unit to debut in Heroes prior to being eligible for the Choose Your Legends voting competition, following Altina and Bramimond.
- Ullr shares her Japanese voice actress, Kuwashima Houko, with Genealogy of the Holy War's Tailtiu.
- See main article: Ullr/Gallery.