Chris Bohjalian has written a compelling new novel that is part love story, part history lesson. And the history is his own.

In The Sandcastle Girls, Bohjalian offers an eye-opening tale of longing and discovery set during an event in history that is still not widely known: the slaughter of hundreds of thousands of Armenians near the beginning of World War I.

Bohjalian, a critically acclaimed writer with Armenian grandparents, is staking out serious political territory in this novel. The deaths of as many as 1.5 million Armenians at the hands of the Ottoman Turks in Syria, a mass killing that began in 1915, remains an emotionally and politically charged topic almost 100 years later. The term “genocide” — which Bohjalian uses to describe the deaths in an author’s note at the end of his book — has been rejected by Turkey because the government insists there is no evidence of a systematic extermination of a people. Even in the United States, where a strong Armenian community lives, a 2007 effort by congressional lawmakers to officially condemn the genocide failed after pressure from the Bush administration over Turkey’s role as a key U.S. ally.

For Bohjalian, there is no debate. Genocide is the right word, and his novel is his argument. But even though the descriptions of the brutality are devastating — Armenians were executed by soldiers, killed by neighbors, marched into the desert to die — the book isn’t a lecture. Instead, it’s a bittersweet reflection on hope even in the darkest circumstances.

We see the mass killings through the eyes of a young woman from Boston who arrives in Aleppo, Syria, in 1915, armed only with a few Armenian words and the determination to help deliver food and medical aid to the refugees. During her work with the Boston-based Friends of Armenia, she meets an Armenian engineer who has lost his wife and child. As the refugees are marched into the city, walking skeletons with barely a flicker of hope to keep them alive, two people from different worlds — the wealthy American, Elizabeth, and the shell-shocked engineer, Armen — begin to fall in love. But Armen decides he must join the fight with the British, so the would-be lovers are parted, at least for now.

When the novel switches to present day, we begin to see the genocide with a more distant perspective. A novelist named Laura Petrosian, living in suburban New York, starts digging into her own Armenian roots after an odd call from an old roommate who says she saw a photo of Laura’s grandmother in a newspaper. But the photo turns out to be someone else — a woman with Laura’s last name. As Laura tries to figure out who the woman is, she begins to unearth parts of her grandparents’ past that had been hidden for decades.

The story, alternating between Elizabeth in Allepo and Laura in New York, does a remarkable job of showing readers the epic scale of what Bohjalian calls the “Slaughter You Know Next to Nothing About.” Elizabeth’s view is at ground level during the roundup of Armenians: flies settling on half-dead bodies, columns of shuffling refugees forced into the desert, naked women with open sores long past the point of modesty and orphans struggling to survive with skinny limbs and enormous eyes.

Laura’s perspective comes through the survivors, refugees in the United States that include her grandparents with their hookah pipes, plush oriental carpets and leather-bound books in a language she couldn’t read, all housed in a living room she calls the Ottoman Annex. Through her, we feel the remnants of sadness, the “subterranean currents of loss” that know no geographical borders.

“If you are not Armenian, you probably know little about the deportations and the massacres: the death of a million and a half civilians. Meds Yeghern. The Great Catastrophe. It’s not taught much in school, and it’s not the sort of thing most of us read before going to bed,” Bohjalian writes, explaining in Laura’s voice.

Survivors of genocide feel ties to the past, he notes — a responsibility, even — that others without such a loaded history might simply shrug off. As the 100th anniversary of the slaughter approaches on April 24, 2015, he reminds us that “history does matter. There is a line between the Armenians and the Jews and the Cambodians and the Serbs and Rwandans. There are obviously more but, really, how much genocide can one sentence handle? You get the point.”

We do. Bohjalian’s book is about the ways the past informs the present, about the pain but also the richness of heritage. If his goal is to educate us, make us see what has been almost left behind in the dust of history, he succeeds. And after reading this book, we aren’t likely to forget.

Amy Driscoll is a Miami Herald editor.