Ursa was born into Clan Wren. Her husband was from a lesser family so he took her name when they married, and she passed the "Wren" surname down to their children like Sabine.
When her daughter Sabine spoke out against the Empire for using weapons she helped create on fellow Mandalorians, Sabine's family, including her mother, chose to follow the Empire instead of her. Deeply hurt by this, Sabine fled Mandalore, and Ursa was forced to deal with the disdain of the other clans for what they perceived as her daughter's betrayal. Ursa's husband was forced to stay on Mandalore as a captive of Gar Saxon, while Ursa's son Tristan joined the Imperial Super Commandos as a means of improving their family's standing. Saxon would later tell Sabine that Ursa had sided with him, though Sabine retorted that she "doubt[ed] [Saxon] gave her much choice."
Ursa was unpleasantly surprised when Sabine and her Rebellion comrades Kanan Jarrus and Ezra Bridger arrived on Krownest, and ordered Sabine imprisoned; she was then stunned when Sabine revealed her possession of the Darksaber. After confiscating the lightsabers of the two Jedi, Ursa granted them an audience, in which she expressed her belief that the presence of the Rebels would bring greater trouble to Clan Wren. She later took Sabine aside for a private conversation, and after learning that she had not won the Darksaber from Maul expressed her belief that no one would follow Sabine's lead. She then revealed what had become of Sabine's father, and that she had felt Sabine safer on the run; Sabine then expressed her determination to stand against the Empire.
Ursa later responded to a transmission from Sundari and spoke with Gar Saxon, and offered him the two Jedi in exchange for Sabine's safety. However, after Saxon arrived, he announced his intentions to wipe out Clan Wren along with the Jedi, but was fortunately thwarted due to the intervention of Fenn Rau, who had accompanied Sabine to the planet but remained in hiding. With the aid of the rearmed Jedi Clan Wren fought against Saxon's commandos, though Ursa later prevented Ezra from going to Sabine's aid as she faced Saxon. Sabine defeated Saxon but was nearly killed by him, but Ursa shot the Imperial Viceroy to save her daughter's life. Now reconciled, the family prepared to face the chaos that would result from Saxon's demise, with Ursa declining to aid the Rebellion directly and Sabine and Rau electing to stay with Clan Wren to help Mandalore throw off Imperial rule.
- "The Protector of Concord Dawn" (Indirect mention only)
- "Imperial Super Commandos" (Indirect mention only)
- "Trials of the Darksaber" (Indirect mention only)
- "Legacy of Mandalore" (First appearance)
- "Zero Hour"
- She is voiced by Sharmila Devar.
- According to the Rebels Recon featurette for The Protector of Concord Dawn, Ursa was present when Darth Maul killed Pre Vizsla - one of the Death Watch members who didn't remove her helmet. Ursa's armor shares its design-though not coloration-with that of Rook Kast, a subordinate of Gar Saxon's in the Darth Maul: Son of Dathomir comics, and some fans believed that Ursa might indeed be Kast until her name was revealed.
- Ursa means "bear" in Latin - perhaps a reference to her role as a "mama bear" defending her daughter Sabine.