[12] The book explores post-colonial Nigeria during a military coup d'état, examines the cultural conflicts between Christianity and Igbo traditions, and touches on themes of class, gender, race, and violence.

[33] The novel expands on the Biafran conflict, weaving together a love story that includes people from various regions and social classes of Nigeria, and how the war and encounters with refugees changes them.

[34] The stories focuses on the experiences of Nigerian women, living at home or abroad, examining the tragedies, loneliness, and feelings of displacement resulting from their marriages, relocations, or violent events.

[51] For example, in Purple Hibiscus, the arrival of a king to challenge colonial and religious leaders symbolises Palm Sunday,[52] and the usage of language referencing Chinua Achebe's Things Fall Apart invokes the memories of his work to her readers.

[54] To describe pre- and post-war conditions, she moves from good to worse as seen in Half of a Yellow Sun, in which one of her characters begins by opening the refrigerator and sees oranges, beer, and a "roasted shimmering chicken".

[74] For example, in Purple Hibiscus, the character Auntie Ifeoma embodies a womanist view through making all family members to work as a team and with consensus, so that each person's talents are utilised to their highest potential.

Half of a Yellow Sun, her major work on the war, highlights how policies, corruption, religious dogmatism and strife played into the expulsion of the Igbo population and then forced their reintegration into the nation.

In it, she evaluates themes of identity that recur in Purple Hibiscus, Half of a Yellow Sun, and The Thing Around Your Neck such as stereotypical perceptions of Black women's physical appearance, their hair and their objectification.

Her work discusses homosexuality in the context of marital affairs in stories such as "Transition to Glory", and taboo topics such as romantic feelings for clergy in Purple Hibiscus, as well as the seduction of a friend's boyfriend in "Light Skin".

[108] The story examines the failure of contraception and an unexpected pregnancy, abandonment by her partner, single motherhood, social pressure and Zikora's identity crisis, and the various emotions she experiences about becoming a mother.

"[112] The western concept contrasted with her upbringing in Nigeria, because in West Africa the attention that a person pays to their fashion and style correlates to the amount of prestige and respectability they will be given by society.

[117][118] That year, Maria Grazia Chiuri, the first female creative director of French fashion company Dior, featured in her debut collection a T-shirt with the title of Adichie's TED talk, "We Should All Be Feminists".

[119][115] Adichie was surprised to learn that Dior had never had a woman rule its creative division and agreed to a collaboration with Chiuri, who invited her as an honoured guest to sit in the front-row of the company's spring runway show during the 2016 Paris Fashion Week.

He stated that allowing Dior to feature her text was a skillful way to use various media forms to not only deliver political messaging, but also to develop her image as a multi-faceted intellectual, literary and fashionable "transmedia phenomenon".

[122] In her 2016 Facebook post Dear Ijeawele, or A Feminist Manifesto in Fifteen Suggestions, Adichie argued that minimising femininity and its expression through fashion and makeup is "part of a culture of sexism".

[134][135] In her article, "Sognare come un'unica umanità" ("Dreaming as a Single Humanity"), Adichie recalled being berated at her mother's funeral for having criticised the church's focus on money, but she also acknowledged that Catholic rituals gave her solace during her mourning.

[139][140] Writer Bernard Dayo said that Adichie's eulogy to Wainaina in 2019 perfectly captured the spirit of the "bold LGBTQ activist [of] the African literary world where homosexuality is still treated as a fringe concept.

[137] After the apology, Adichie attempted to clarify her statement,[137][d] by stressing that girls are socialised in ways that damage their self-worth, which has a lasting impact throughout their lives, whereas boys benefit from the advantages of male privilege, before transitioning.

[142] Adichie admitted in an interview with Otosirieze Obi-Young in September that she was "deeply hurt" by the backlash and began a period of self-reflection on her biases, informed by reading anything she could find to help her understand trans issues.

[161] Adichie accepted an invitation to speak in London in 2012,[162] at TEDxEuston, because a series of talks focusing on African affairs was being organised by her brother Chuks, who worked in the technology and information development department there, and she wanted to help him.

[163] In 2015, Adichie returned to the theme of feminism at the commencement address for Wellesley College and reminded students that they should not allow their ideologies to exclude other ideas and should "minister to the world in a way that can change it.

[166] Adichie was the first African to speak at Yale University's Class Day, giving a lecture in 2019 that encouraged students to be open to new experiences and ideas and "find a way to marry idealism and pragmatism because there are complicated shades of grey everywhere".

Her speech was given in the Nelson Mandela barrio, one of the poorest neighborhoods of the city, and she encouraged Black women to work with men to change the violent culture and celebrate their African roots.

[181] She was the keynote speaker of the 2021 Reykjavik International Literature Festival held in the Háskólbíó cinema at the University of Iceland, and presented the talk In Pursuit of Joy: On Storytelling, Feminism, and Changing My Mind.

[12] In an earlier article published in Brittle Paper, he stated that Half of a Yellow Sun's paperback release in 2006 sold 500,000 copies, the benchmark of commercial success for a book, by October 2009 in the UK alone.

[188] According to Lisa Allardice, a journalist writing for The Guardian, Adichie became the "poster girl for modern feminism after her 2012 TED Talk 'We Should All Be Feminists' went stratospheric and was distributed in book form to every 16-year-old in Sweden".

"[190] She later refined the statement in an interview with the Dutch newspaper De Volkskrant, saying that she liked and admired Beyoncé and gave permission to use her text because the singer "reached many people who would otherwise probably never have heard the word feminism."

"[192] Scholar Matthew Lecznar said that Adichie's stature as "one of most prominent writers and feminists of the age" allowed her to use her celebrity "to demonstrate the power of dress and empower people from diverse contexts to embrace [fashion] ... which has everything to do with the politics of identity".

[136][76][155] Journalist Shreya Ila Anasuya described Adichie's public speaking as delightful and articulate, noting that her timing allowed sufficient pauses for the audience response, before she continued by distilling "her wisdom into the simplest and most compassionate of telling".

[209] Scholar Grace Musila said Adiche's brand encompasses her reputation as a writer, public figure, and fashionista, which expanded her reach and the legitimacy of her ideas far beyond academic circles.