Americanah features the experiences of a Nigerian woman, Ifemelu, who lives in the United States for ten years and then moves back to Nigeria. The novel covers her life in Nigeria before emigrating, the years spent in America, and how her life changes after she returns home. The novel also explores the similar, but not exactly parallel, experiences of Obinze, a man who is Ifemelu’s lover at various times in Lagos, including his temporary residence in England.
Exclusion is portrayed as both overt and blatant, covert and subtle. Ifemelu had anticipated that she would face racism in the United States but was unprepared for the undercurrents of discrimination that she encountered at different levels of society. This includes employment discrimination. Although she is a university student, she does not easily find work, and, when she does, she faces negative assumptions about her sexuality.
In many respects, Ifemelu feels comfortable within a multiracial society and has a white male romantic partner, Curt; in that situation, class as well as race was a factor in excluding her from his life and family. However, she finds that there is a separation between African Americans with a deep heritage of living in the United States and African immigrants. Such differences affect her relationship with Blaine. Beyond that, national and ethnic or tribal differences are also factors of exclusion.
Upon returning to Nigeria, Ifemelu finds herself excluded and alienated from her previous social circles. Former friends reject the authenticity of her experience because they consider her Americanized and snobby. Ifemelu is drawn to renew her relationship with a former lover, Obinze, in part because his experience living in England has given him insights into the immigrant experience.