WH Auden once said it was a “fallacious belief that art ever makes anything happen”. Had there never been any art, he claimed, “the history of man would be materially unchanged”. Wayétu Moore, however, believes differently. The Liberian-American author and social entrepreneur opened her own bookshop, One Moore Bookstore, Liberia’s first dedicated to reading for pleasure. She started One Moore Book, a non-profit publisher of children’s books for underrepresented communities, after seeing first-hand how children engaged better with characters that look like them. And somehow she also found time to write a novel: She Would Be King, a fantastical retelling of Liberia’s founding. “It was in reading that I was able to make sense of my new country,” Moore says of her early days in the US. “Representation is important.”

As Africa’s first independent republic, Liberia began as a settlement of the American Colonisation Society, which believed freed African American slaves would fare better there.

Born in Monrovia in 1985, Moore was four years old when the first Liberian civil war broke out. The seven-year conflict would kill 250,000 people and displace around half of the country’s 2.1 million population. Moore was living with her father and sisters at the time, while her mother, a Fulbright scholar, was studying abroad at Columbia University. “We left Monrovia and hid in a village for six months before my mother was able to send someone to get us across the border,” Moore says. At five, she found herself living in her mother’s Upper Manhattan dorm before the family eventually settled in Texas, where she spent her formative years.

Growing up with her father’s stories of the “profound experiment” of Liberia, Moore knew she wanted to unpack it through literature. But outside her own household, she barely heard anyone speak of her home country. “Not learning about Liberia in my Texan public schools was a form of erasure that deserved to be rectified,” she says. “So when I realised I wanted to be an artist, and began to write, Liberia was one of the first places I went to.”

She Would Be King has been described as a “magical realist” take on Liberia’s history, by everyone from the New York Times to her own publishers, placing Moore’s book in the same tradition as One Hundred Years of Solitude, Nights at the Circus and Midnight’s Children. But there is a problem with this. “Magical realism is the term that’s being used to describe works by contemporary African writers that engage with supernatural beliefs and abilities,” Moore says, “but the issue is that these kinds of stories existed before the category formally did … It was rare in the west African storytelling tradition to hear a story that didn’t include someone casting a spell, or flying or shape-shifting or displaying some other supernatural ability as they went about their lives.” Works with fantastical elements are being force-fitted into one category, when they are, in fact, drawing from another source. “I don’t mind when it’s categorised as magical realism,” she says. “But I also recognise that when African and black diaspora writers engage with the art in this way, it is older and larger than the category.

The novel’s plot is divided between three characters: Gbessa, an indigenous woman of the Vai people; June Dey, an African American slave; and Norman Aragon, the child of a Jamaican Maroon and an abusive Englishman. Each has a gift that reflects their cultural experience, a kind of physical metaphor. The Maroons fled up the mountains and camouflaged themselves in nature, and so Norman can become invisible. June Dey has superhuman strength, reflecting the resilience of African Americans. Gbessa is immortal, but can still feel pain. “It’s said that the first human was sub-Saharan African,” Moore says, “so these groups have existed since the beginning of time, and because of the reverence for ancestors, some believe their spirits outlive a physical body, making them immortal. Gbessa’s ability speaks to that.”

“The coastal village of Lai had only seen one woman as cursed [as Gbessa],” writes Moore – Ol’ Ma Famatta, “the first of the Vai witches”, who “they say is sitting in the corner of the moon after her hammock flung her up there on her 193rd birthday”. Her story makes Gbessa “feel less unusual, more human”; she sees a reflection of herself and finds comfort. Moore has felt the same: “The ability to see oneself immortalised in storytelling has had a powerful impact on me. It gives me a sense of belonging to this world … My hope for She Would Be King is for Liberians to read it or see it on the shelf of a local bookstore and think, ‘There I am.’”

But to discuss She Would Be King in purely utilitarian terms would neglect its lyricism, and the cinematic scope of its story. This is not a textbook: it is riveting fiction about a fascinating country. And it is also timely. She Would Be King, about the founding of a nation, has arrived in a time of increased nationalism. But far from being a founding myth, it is a deconstruction of the tensions that lie at the heart of nationhood. Particularly how national identities can subsume the historic cultures of a nation. Gbessa, a Vai woman, later finds herself in a position of power and tells some tribal workers in English: “No Bassa, no Kpelle, no Vai people on my farm … We Liberian here.”

Moore says: “Liberia also has a history that is ritually packaged for mass consumption, and that packaging neglects nuance, and sometimes even the humanity of Liberians. I wanted to tell the truth ... commitment to truth from different perspectives is a remedy for the pervasive isolationism that is spreading internationally. Truth is the most humanist commitment we can make.”

• She Would Be King by Wayétu Moore is published by Pushkin Press. To order a copy, go to guardianbookshop.com. Free UK p&p on orders over £15.