How do the humanities relate to the book?

Junot Díaz's best-selling novel, The Brief Wondrous Life of Oscar Wao, addresses many areas of the humanities, including (but not limited to) history, politics, art and culture, and gender relations.
Much of the plot of the story directly involves the Dominican Republic's culture and history, because the main characters and/or their ancestors hail from the Dominican Republic. Diaz introduces the audience to the history of the Dominican Republic in the twentieth century and its oppressive dictator Rafael Trujillo, who plays a role in shaping the life of Oscar's family. We find out many quirks of the culture, most notably "fuku," a sort of curse or witchcraft that dooms a person or a family.
A major aspect of the story is nerd culture, a sort of subsection of humanities, since the protagonist Oscar is very much into all aspects of nerd culture, such as video games, science fiction, and anime. Many aspects of this culture are referenced throughout the story, often without further explanation, leaving the reader to either understand the reference or be confused.
Finally, the story identifies many areas of gender relations, primarily in Dominican culture but also across the broader United States. While Oscar is not lucky with the girls, the narrator is, and relations between girlfriends, sisters, mothers, and aunts are clearly laid out and commented on. The "machismo" culture of the Dominican Republic is analyzed and criticized throughout the story.