Every place Geraldine Brooks has ever lived has given her a book, but up to now they have come at a lag. She wrote her first book, Nine Parts of Desire, about Muslim women in the Middle East, after she had left her Wall Street Journal post there and was living in London. She wrote her memoir about growing up in Australia, Foreign Correspondence: A Pen Pal’s Journey from Down Under to All Over, while living in Virginia, and the Pulitzer prize-winning novel March, which is in many ways about that Virginia community and its idealists in the Civil War, she wrote after she’d moved to Massachusetts.

Her forthcoming novel, Caleb’s Crossing, is born of Martha’s Vineyard, where Ms. Brooks has been a full-time resident for about five years and sometimes resident for decades. “This is the first time the writing and the life have really come together in real time, and it was fantastic,” she said by the hearth of the 1720 West Tisbury home where her family recently moved, from downtown Vineyard Haven.

For the past three years, Ms. Brooks has walked two Islands, Martha’s Vineyard as it is now and as it was in the mid-1600s, as herself and as her young English narrator, Bethia. “I made this Island mine, mile by mile, from the soft, oozing clay of the rainbow cliffs to the rough chill of the granite boulders that rise abruptly in the fields, thwarting the plough, shading the sheep,” Bethia says. “I love the fogs that wreathe us all in milky veils and the winds that moan and keen in the chimney place at night. Even when the wrack line is crusted with salty ice and the ways through the woods crunch under my clogs, I drink the cold air in the low blue gleam that sparkles on the snow. Every inlet and outcrop of this place, I love.”

Like Bethia, Ms. Brooks has a potent response to her adopted landscape. “The first time I ever walked under those cliffs in Aquinnah . . . you know, in your guts, even before you learn about Moshup, that this is a place that’s been sacred and powerful for a long time.”

She is also especially fond of another walk where, when she gets to a certain high point, “for some extraordinary reason you can see from one end of the Island to the other, from the north shore to the south shore, and when you’re up there you can’t see one manmade thing.

“It’s not that it’s identical to the 17th century — it can’t be, because the forests have changed so much and this is all regrowth,” said Ms. Brooks, who has been on the Vineyard Conservation Society board. “But apart from that, you could imagine yourself being Bethia, or Caleb, and seeing that exact same view, of water meeting land on two sides of the Island.”

Caleb is Caleb Cheeshahteaumauk, the first Native American to graduate from Harvard University. Ms. Brooks first learned of him on an Island map published by the Wampanoag Tribe of Gay Head (Aquinnah) that noted his 1665 achievement. Initially she read it as 1965, 300 years later than the date of his commencement. “My eye transposed the number because it just didn’t make sense to me,” said the Australian-born author. “Not having grown up here, I had no idea Harvard even existed in 1665. I mean, that’s 100 years before the white history of Australia, and they’ve already got a college!” she said.

Caleb wouldn’t let go of her imagination and his story became the inspiration for her latest novel, which will be released May 3.

And so she came to take on the story of the first European settlement on the Island called Noepe by its native people; not just any story about Martha’s Vineyard, but The Story, really.

Her new work of fiction considers — through the Caleb she imagines (little written history survives of his life) and the likewise conjured young daughter of the Island’s missionary (called Mayfield in the novel) — how Islanders, the natives and the newcomers, came to know each other in the very earliest years.

“The first contact period, it’s part of the American story, it’s part of the human story, it’ll be part of our story in the future when we make contact with another intelligence somewhere in the universe,” she said. “I’ve always been fascinated by the first meeting of people who haven’t known anything about each other.”

So many years later, that cultural chasm still requires a delicate straddle.

The program director for the Aquinnah Cultural Center, Linda Coombs, said this week, “I just think that, given our history and all the misrepresentations there have been in last 400 years, in my perception people shouldn’t fictionalize about it.”

The Wampanoag tribal historic preservation officer, Bettina Washington, added, “I’m a little worried that people may, even though it’s a work of fiction, take some of the things as fact.”

This is Ms. Brooks’s fourth book of historical fiction, after Year of Wonders, March and People of the Book, and debate about the appropriateness of imagining the unknowable past is not new to her. “I believe in fiction,” she responded.

She remembers what the African American writer James Baldwin, said in defense of William Styron, when he provoked outrage by imagining himself a slave in The Confessions of Nat Turner: “Each of us, helplessly and forever, contains the other — male and female, white and black, black and white. We are part of each other.”

“That’s what I believe,” Ms. Brooks said, adding: “It’s the strong emotions that shape us, and I don’t think they change no matter what race you are and no matter what period you live in.

“I do embrace the necessity for great respect and for not assuming ownership of the story — and I don’t — but I wanted to write this to honor Caleb’s incredible achievement and his struggle and his sacrifice.”

Ms. Washington said nevertheless, “I’m more than a little concerned. Every tribal member has their own understanding and perception of history, but when you come through my office it is the official tribal voice.”

Ms. Brooks does rely on voices. She prefers to write her novels in the first person. “So I have to hear a voice, and I didn’t think I was going to hear his voice.

“Caleb is a figure that crossed into English culture. So I don’t think he would speak to me in the language of his heart, but he had many languages in his life, including English and Latin, so I thought maybe he would speak to me as he spoke to other English people in his life,” she said.

“I really believe that the human heart is the human heart, and I don’t believe in an apartheid of the imagination but I also didn’t think I could do [Caleb’s voice] justice.

“Other fiction writers have been drawn to him and will be again and hopefully somebody from the tribe will hear his voice . . . but I wanted to write from the point of view of the English settlers. I thought maybe I could hear that voice in my head.”

Her Bethia, a girl who yearns for learning denied to her sex in her time, is shaped not only by Ms. Brooks’s exhaustive research of colonial documents, letters, history and oral history, but also from her years as a foreign correspondent. “Bethia’s quest for education is not unlike what a lot of girls in very repressive Muslim regimes still do,” she said, adding: “The beauty of fiction is you do draw on absolutely everything, and you sort of metabolise it.”

The book is dedicated “For Bizuayehu, who also made a crossing.” Bizu, now in second grade at the Tisbury School, is her son. He came from Ethiopia some three years ago to this family, with his brother, Nathaniel, a freshman in high school here, and father, fellow writer and Pulitzer-winner Tony Horwitz.

It turns out that Caleb’s crossing specifically is closer to her family than Ms. Brooks first realized. “I found out in the course of researching the book that one of my several great-grandfathers almost certainly knew Caleb,” she marvelled.

She is a descendant of Ephraim Cutter, brother in law of Elijah Corlett, who ran the Cambridge prep school Caleb attended. “Ephraihm Cutter was a glazier in Cambridge at that time, so he would have been seeing his sister and presumably he met the pupils at the school . . . so I wrote him in. He fixes a broken window at Harvard,” she said.

“Not that I intended it, but it turned out that I did have a horse in the race after all, and I am responsible for the dispossession,” she said, knowing too well the crushing detail of the colonial legacy here.

“We like to think that this Island was a little better. And it was a little better. But it wasn’t so great. The dispossession was not a bloody massacre but it was gradual and it was reprehensible. Debt peonage, the way people were exploited by the private property system and their children were indentured away from their family and their culture and their language, and the unintended consequences of disease, and the emasculation of what was an absolutely magnificent and thriving and abundant culture.”

Bethia’s view, which Ms. Brooks says echoes the writings of many Islanders of the time, is one of envy for the quality of life the Wampanoag had in the physical world. That they were handsome and healthy and had plenty of food and leisure. “It was an abundant culture, a culture alive with spiritual richness,” the author said. “But because these people were religious Puritans, there was also a certain, ‘But of course they’re lost, we have to save them, you know, God’s abandoned them to the devil.’ ”

Forced to live with these two worlds, Caleb chose to take an English education. “And it was a rugged course of study,” Ms. Brooks explained. “You had to be fluent in Latin, you had to be able to take all your classes in that language, then you had to master Greek, you studied all the classic literature, you learned Hebrew or Aramaic, you learned astronomy and what passed for natural history at the time. You worked essentially six days a week and on the Sabbath you had to pay attention to the sermon because you would be tested on it. And at the end of your four years, the exam was that you had to sit in the hall for six days and anyone who had a university degree could come in and quiz you and see if you had adequate knowledge to get your BA. So this was no small achievement.”

As the novel says in an afterword, two Vineyard Wôpanâak, Carrie Anne Vanderhoop and Tobias Vanderhoop, successfully completed Harvard graduate degrees in recent years. And in May, Tiffany Smalley, the first VineyardWôpanâak since Caleb Cheeshahteaumauk, will be awarded an undergraduate degree from Harvard.