- Ugwu – The first protagonist of the novel, a young village boy from Opi. He works as a houseboy for Odenigbo, who helps Ugwu continue his education and improve his writing skills. He is a hopeless romantic and allows love to control his life at times. However, he undergoes a dramatic transformation when he is forced into the Biafran army, where he witnesses extreme violence and trauma.
- Odenigbo – In the beginning of the novel, Odenigbo is a Professor of Mathematics at Nsukka University. He is considered revolutionary to his peers because of his support for socialism and Pan-Africanism. After leaving Nsukka University in the wake of the war, he actively becomes a Biafran patriot. Odenigbo later marries Alanna, but cheats on her with Amala.
- Olanna Ozobia – Olanna is one of three protagonists the novel’s storyline revolves around. She was raised in Nigeria and is the daughter of Chief Ozobia. Her beauty often affects how men treat her, but she later finds love with Odenigbo. Throughout the war, she works in refugee camps and teaches children.
- Kainene – Kainene is Olanna’s twin sister but is quite different from her. She is strong, responsible and independent, taking on her father’s business in Port Harcourt. After seeing the brutal conditions of the war, she decides to open a refugee camp.
- Richard Churchhill – Richard is an English journalist who falls deeply in love with Kainene. His interest in Nigeria began when he discovered ancient Igbo-Ukwu art and pottery. Although he feels connected to Biafran culture, he struggles to realize he will never be able to truly understand the suffering of Biafran people. Richard utilizes his privilege to bring attention to the war through his articles.
- Odenigbo’s Mother (Mama) – A village woman who is unfamiliar with Odenigbo's modern life and education. Mama wants Odenigbo to have a child with Amala because she thinks Olanna is a witch. When she refuses to leave her village, she is killed during the war.
- Amala – The girl who Mama wants Odenigbo to have a child with. Eventually, Amala agrees to help Mama and bears Odenigbo's child.
- Chiamaka – Odenigbo and Amala's child. Olanna ends up taking Chiamaka and raising her as her own daughter.
- Madu Madu – A good friend of Kainene. He is tall, confident, and a colonel. Richard is jealous of him.
- Eberechi – One of Ugwu's love interests. Ugwu falls in love with her while he is in Umuahia.
- Susan Grenville-Pitts – Richard’s first girlfriend whom in Nigeria. Susan is a racist English woman who a jealous who looks down on Nigerian culture.
- Chief Ozobia – Olanna and Kainene’s father. He is wealthy Nigerian businessman.
- Mrs. Ozobia – Kainene and Olanna’s mother. She is very beautiful and vain.
- British Colonialism in Nigeria – The Biafran War began shortly after Nigeria gained independence after British colonial rule. Colonialism in Nigeria birthed a new, divided country with no sense of unity. Although Nigeria seemed to be free from British rule, the British remained a strong factor in determining the nation's social, political, and economic state. Regarding the war, the British bribed Nigeria with weapons and even encouraged Nigeria to create an observer team to plan genocide in Biafra. Adichie communicates the violent history of British colonialism through Odenigbo, who is considered a radical for being a patriotic Biafran. Odenigbo strongly opposes the abuse of power by the British and comments on colonialism's impact on Nigeria's development as a nation. The Biafran War killed millions of people and brought permanent trauma, stemming mainly from British powers sparking ethnic tensions and distributing weapons.
- Love – Although the novel contains violence and the brutalities of war, Adichie balances out her writing by making love a recurring theme. Despite the negative transformations each character undergoes, love remains a crucial aspect of their lives. Adichie includes many romantic relationships, such as Olanna and Odenigbo, Kainene and Richard, and Ugwu's several crushes and infatuations. The most important part about love being so present in the novel is that it complements the historical backdrop of war and Nigeria's political state. The romantic relationships cannot be separated from these historical and political events; for example, Richard is forced to confront and utilize his white privilege, and Odenigbo inspires Olanna to take interest in global issues. In contrast, Adichie highlights how war and violence often stole people's loves by tearing them apart from their families and partners.
- War and Violence – War and Violence is a central theme in Half of a Yellow Sun as the novel does take place prior to and during the Nigerian Civil War. One of the key events that catalyzed the war occurred in 1966, when thousands of Igbo people were massacred. Although Biafra was created in order to restore the Igbos' faith and community, Nigeria rejected this notion by declaring war. Additionally, the British supported the Federal Military Government of Nigeria (FMG) to commit genocide by providing funding for military supplies. An estimated one to three million people died while fighting in the Biafran war, yet this part of African history is often neglected or completely erased. In the novel, Adichie depicts the daily traumatic experiences people faced, such as watching family members get decapitated and raped. The danger and violence in Nigeria also forced people to quit their jobs, cease their education, and migrate; this caused families to be torn apart. For example, the first protagonist, Ugwu, initially works with Odenigbo to become literate and continue his education. He is curious, passionate, and brilliant. However, his life drastically changes when he is forced to join the army; Ugwu is permanently traumatized after he participates in a gang rape. The novel addresses these horrific stories, ones that are often ignored even in the African education system.
Ugwu:
"Oh. That is toothpaste. We use it to clean our teeth." Ugwu felt proud saying we, so that his mother would know he too used it. But she did not look impressed…"What is wrong with using a good atu?" ― Half of a Yellow Sun, pg. #116
Odenigbo:
The real tragedy of the postcolonial world is is that the majority of people had no say in whether or not they wanted this new world; rather, it is that the majority have not been given the tools to negotiate this new world. ― Half of a Yellow Sun, pg. #129
Kainene:
Of course I asked because you are white. They will take what you write more seriously because you are white. ― Half of a Yellow Sun, pg. #382
Olanna:
She was used to her mother’s disapproval;…when she refused to marry Igwe Okagbue’s son, and later, Chief Okaro’s son. ― Half of a Yellow Sun, pg. #46
Kyna Smith 2019