|Full Name||Nagisa Chiba
|Age||28 (first Season), 29 (at R2), 26 (in game)|
|Date of Birth||a.t.b. September 1, 1988|
|Title||Member of the Four Holy Swords
Captain of the Fourth Squad
| Burai Kai|
Akatsuki Command Model Zikisan
|First Appearance||Battle for Narita|
|Voiced by||Saeko Chiba (Japanese)|
Laura Bailey (English)
|See The Black Knights|
Nagisa Chiba (千葉 なぎさ or 千葉凪沙, Chiba Nagisa), 28 years old (29 at R2), is the sole female member of the Four Holy Swords. She later joins the Black Knights and after the restructuring of the Black Knights, she becomes Captain of the Fourth Squad.
She is a member of the elite unit known as the Four Holy Swords and was also a member of the JLF intially. In order to rescue Tohdoh, she along with the other members of the Four Holy Swords joined the Black Knights. She also holds a strong attraction to Kyoshiro Tohdoh. A year after the Black Rebellion, she harbors animosity towards Zero for abandoning them. She survives the final battle but is captured along with all the other Black Knights for a public execution. She is released when Lelouch is killed and is seen together with Tohdoh in traditional Japanese attire in a photo of Kaname Ohgi's wedding.
Chiba makes her first appearance along with Kyoshiro Tohdoh and the Four Holy Swords to defend the Japan Liberation Front from the Britannian Army. She is piloting a Burai Kai, an upgraded version of the Burai. While defending, Zero retreats leaving Tohdoh and the Four Holy Swords to fend by themselves. As a result, they abandoned their knightmares and escape. She is later seen with Tohdoh and the others for a meeting, but are discovered and Tohdoh sacrifices himself and becomes captured to let Chiba, Urabe, Asahina and Senba escape. Then, the Four Holy Swords turn to the Order of the Black Knights for help to rescue Tohdoh.Chiba and the Four Holy Swords are given the Gekka to pilot by Rakshata. They break into the prison and rescue Tohdoh. Then, Chiba fights against Suzaku with Tohdoh and the others. Tohdoh and the Four Holy Swords' knightmares take damage due to the Lancelot's Harken Boosters. They spot reinforcements and Tohdoh gives the command to release the chaffsmoke and escape.
She is seen later on after Euphemia massacres the Japanese due to Lelouch's Geass and follows under Tohdoh during the Assault on Tokyo Settlement. She appears with Tohdoh and strategizes on what to do next. During the time that Zero has left, she is pinned down with Asahina by Britannian Forces.
After the failed rebellion, Chiba was arrested along with the other members of the Black Knights. To draw out Zero,Gilbert G.P. Guilford threatens to publicly execute all of the Black Knights. However, Zero does come, but manages to free them all. Because of Zero's earlier abandonment, Chiba has a harder time to trust Zero, but because of Tohdoh still follows under his command. She is later seen during the assault on a Britannian aerial transport of Viceroy Nunnally to kidnap her. She witnesses when Kallen falls off the airship and tells her to pull the ejection seat. Following that, Chiba is caught by the Mordred and ejects right before her Gekka is destroyed.
During the time when the Black Knights are in the Chinese Federation, Chiba obtains the knightmare, Akatsuki Command Model Zikisan to replace her Gekka and to fight against the Chinese Federation forces with it. During the Battle at Xiaopei, Chiba and Asahina were able to ambush the Chinese Federation forces. However, after the Shen-Hu makes an appearance both her and Asahina are overwhelmed by its power and she watches helplessly as Kallen is taken prison. She regroups with the remaining Black Knights at the Mausoleum of Eighty-Eight Emperors where another battle ensues between the Black Knights and the united forces of the Holy Britannian Empire and the Chinese Federation. She along with Tohdoh and Asahina are left in charge of destroying the air units as well as engaging in battle with the Knights of the Round. During the battle, Chiba along with C.C. both strike the Mordred and Asahina is able to follow up by damaging the Mordred's Float System. The battle ends after the High Eunuchs are exposed and the Britannian forces retreat.
Before the meeting of the U.F.N., everybody is preparing. Chiba is seen putting on make-up for Tohdoh and was on her way to ask Tohdoh a question hinting on how their relationship is, but Ohgi arrives and Tohdoh leaves while Chiba states that "she was to slow." She later appears in the Second Assault on Tokyo Settlement, under the command of Tohdoh. As the Gefjun Disturbers disable all 5th generation and lower Knightmares, she along with Asahina and Tohdoh try to achieve air superiority over the Britannian government building by destroying the Britannian forces that pilot 6th generation and above Knightmares. When Kallen was set free and was piloting her Guren S.E.I.T.E.N. Eight Elements, she rammed through David T. Darlton's Gareth allowing an opening for Chiba to finish him off. After learning the truth of Zero's identity and his geass power, she joins the other leaders of the Black Knights and betray Zero.
She along with the Black Knights join Schneizel to stop Lelouch's plan. During Tohdoh's battle with Suzaku, his Zangetsu is destroyed, but managed to eject. The cockpit is caught by Chiba who defends Tohdoh by firing missiles at the Lancelot Albion. She manages to escape and bring Tohdoh back to be treated. Tohdoh attempts to join the fight again even though he is badly wounded and Chiba pleads him against doing so. When Lelouch assumed control of the Damocles, Chiba was captured along with everybody who opposed Lelouch's rule. During their scheduled execution, Chiba witnesses Lelouch being assassinated by Suzaku and is released. Chiba is last seen together with Tohdoh while wearing traditional Japanese attire in a photo of Kaname Ohgi's wedding with Villetta Nu.
- She shares the same last name as her seiyū.