Cagalli Yula Athha is the adopted daughter of Uzumi Nara Athha, President and "Lion" of Orb Union. She is also Kira Yamato's twin sister, although neither sibling was aware of this until the Bloody Valentine War. While Kira is a genetically-altered "Coordinator", it is generally believed that Cagalli is a "Natural", which is stated in her official bios on Sunrise-run websites.
In the original Gundam SEED series, Cagalli is first seen disguised as a civilian in Morgenroëte, the military factory where the Earth Alliance's secret mobile suits were being developed. The colony was subsequently attacked by ZAFT forces, who were quite eager to secure the new weapons. Upon discovering the units, she cried that her father was a traitor, presumably for letting Orb develop weapons for the Earth Forces. This was when she met Kira Yamato for the first time since they were separated at birth. Just prior to the destruction of the colony, Kira pushed her into a lifepod.
Cagalli reappeared later in the Bloody Valentine War as a member of the Desert Dawn Resistance Movement in ZAFT-occupied northern Africa. Here she revealed her true identity for the first time as Cagalli Yula Athha, the daughter of the Orb Union president. So in actuality, Cagalli was the Princess of a neutral Earth Nation, although she had decided to fight with the Resistance Movement in Africa on her own terms. During this time she also encountered Kira Yamato again as he spent time on Earth with the Archangel ship. Initially they seemed to clash with one another. However, Cagalli and Kira soon become quite close as they shared a friendly affection for each other.
Sometime later, Cagalli's FX-550 Skygrasper craft was shot down after aiding the Archangel as a pilot in a brief battle against ZAFT forces. In a twist of fate, she was marooned on an island with ZAFT mobile suit pilot Athrun Zala. Initially enemies, they soon called a truce in order to co-exist with one another. However, their different view points pertaining to the war clashed and it didn't seem that they would ever agree. Yet, by sharing their varying opinions, both Athrun and Cagalli began to experience an inner revelation. Was this war really necessary? It was evident how quickly one tragic battle was used as justification for more killing. It was another sad reminder of the needlessness of war for both parties. Not long afterwards, both Athrun and Cagalli were rescued off the island. But, when they parted it was more with fondness than anything else. Little did they know that they shared a mutual friendship with Kira Yamato and would be seeing each other again on several occasions. It's during these encounters that an affection seemed to be growing between the two.
Cagalli eventually joined the crew of the Archangel when the ship arrived to Orb. In the final phases of the Bloody Valentine War she piloted the MBF-02 Strike Rouge as member of the Clyne Faction. Although she is a Natural, in battle she is also capable of going into SEED Mode, like Kira and Athrun.
While on the Archangel Cagalli strengthened her deep bond with Kira, who she later discovers is in fact her twin brother.
Sometime later Athrun Zala abandons his allegiance to ZAFT in order to join the Clyne Faction with Kira. He finally desires to end the war and bring about peace by joining the resistance group. During their time together as part of the Clyne Faction Athrun and Cagalli begin to develop romantic feelings for one another. In fact, during the final battle Cagalli saved Athrun's life in the destruction of GENESIS by reminding him that he has the courage to keep on living.
Two years later, Cagalli reappears in Gundam SEED Destiny...
After the war she was appointed Representative of Orb, but was manipulated by Jona Roma Saran to endorse the alliance between the Earth Alliance and Orb, an alliance that eventually forced Orb to deploy their units against ZAFT forces. With Jona and Cagalli betrothed from young age, by their parents' arrangement, Jona also tried to marry her. Just before the ceremony, Kira "kidnapped" Cagalli and took her again on the Archangel.
The Archangel left Orb, now Alliance territory, and hid underwater until the Dardanelles Battle, where Cagalli in her Strike Rouge tried unsuccessfully to stop Orb's units from attacking ZAFT units. With some encouragement from Lacus she would try again to stop Orb in the Battle of Crete, although she would eventually fail again. At the end of the Battle of Crete, a few defecting Orb soldiers under the orders of the late Captain Todaka joined the crew of the Archangel. Cagalli also used the Strike Rouge to fight in the Battle of Berlin and later used it to retrieve the injured Kira Yamato after the Freedom is destroyed by the Impulse.
When Archangel arrives at Orb, she receives a new high-performance ORB-01 Akatsuki mobile suit that was constructed for her on the orders of the late Uzumi Nara Athha to replace her Strike Rouge after Kira has to take it into space to protect the Eternal. After Orb forces defeat the ZAFT assault in the Second Battle of Onogoro, Cagalli presents a global television broadcast, but is interrupted when "Lacus Clyne" pirates her broadcast. Shortly thereafter, the real Lacus reveals ZAFT's duplicity on global television.
Afterwards because she would be too busy with her responsibilities as Orb's leader, Cagalli was forced to remain behind in Orb when the Archangel was to head into space. However Cagalli handed over the Akatsuki for Neo Lorrnoke to use.
Many fans of Gundam SEED Destiny were outraged that out of all the original characters from Gundam SEED, Cagalli seemed to have the worst lot. Namely, this included being manipulated by Jona, her frequent crying spells, and her abscence from many battles. Even after this character problem appeared to be 'rectified', following her reunion with the Archangel's crew, subsequent appearance in battle and how she took over Orb definitely, fans were still irked at how Athrun and Cagalli were not reunited at the end of the series. Listening to the criticisms of the audience, the production team said they'd be releasing an OVA on Christmas Day that would tie up any loose ends in the Cosmic Era storyline. Apparently this did not happen as, in the OAV, Cagalli was still in Orb and Athrun was last seen leaving the grave yard of Shinn Asuka's deceased family in the company of Meyrin Hawke. This reinforced the speculation that the relationship between Athrun and Cagalli has come to an end, though the creator has not said for sure if it has. Sadly, it also increased the lamentation of some fans, which led them to openly complaining about Fukuda and Morosawa and bashing Meyrin.
- Genetic type: Natural
- Age: 16 (18 at the start of Seed Destiny)
- DOB: Cosmic Era 55, May 18
- Blood type: A
- Height: 162 cm (in GS), 164 cm (in GSD)
- Weight: 54 kg (in GS), 48 kg (in GSD)
- Family: Adopted Father (Uzumi Nara Athha), Brother (Kira Yamato), Father (Ulen Hibiki, deceased), Mother (Via Hibiki, deceased); Possible Brother (Canard Pars)
- Love interests: Athrun Zala
- Pilot of: FX-550 Skygrasper, MBF-02 Strike Rouge, ORB-01 Akatsuki
- Quotes from Gundam Seed (Cagalli):
- "My feelings toward someone have nothing to do with their being Coordinator or Natural." (The Sea Dyed Red: Phase-22)
- "Kill because one was killed, get killed for killing another, do you really think peace will ever come that way?" (Grieving Skies: Phase-31)