Anita Desai has lived in Delhi and London and Boston, but when she settled, she chose the Hudson River Valley, in New York State. She first came 40 years ago, to visit the filmmakers Ismail Merchant and James Ivory, and was so impressed that she later made her home here, on one of the most dramatic stretches of the river.

“I discovered what a beautiful part of America this is,” recalled Desai, 87, sitting in her house in Cold Spring, her living room awash in sunlight and her walls lined with books.

The journey to this point has been long and winding for Desai. For years, she explored a variety of literary and artistic landscapes, from remote Indian ashrams to Mexican mining towns and suburban America, expanding in the process the horizons of generations of Indian writers, both at home and abroad. And now, though she has put down roots in one place, her imagination continues to roam widely.

Her new novella, “Rosarita,” is a slim, enigmatic mystery set in San Miguel de Allende, Mexico, a ghostly meditation on truth and memory, violence and art. In it, a visiting Indian student stumbles upon traces of her mother’s hidden past as an artist in 1950s Mexico — or is it just a mirage, fed by the “fantasies and falsehoods” of a local stranger?

Salman Rushdie has been a deep admirer of Desai’s work since early books such as “Clear Light of Day” (1980), which he said reminded him of Jane Austen. “Both Anita and Austen present a deceptively quiet and gentle surface to the reader,” Rushdie wrote over email, “beneath which lurks a ferocious intelligence and a sharp, often cutting wit.”

“Rosarita” signals a “new departure for Anita,” he added; with its air of mystery and otherworldliness, it suggests Jorge Luis Borges more than Austen.

A sense of foreignness and dislocation has shadowed Desai from the start. The daughter of a Bengali father and German mother, Desai said she never quite fit in with Indian families when she was growing up in Delhi.

She was 10 when India became independent, and she identified powerfully with the mission of the young country. “We were very proud of belonging to this new, independent India. Being part of this country of Nehru gave one great pride and sense of comfort in those years,” she remembered. “But I outgrew that — well, India outgrew that, too.”

When she began writing in the 1960s, she was influenced by a generation of post-independence authors like R.K. Narayan, Raja Rao and Mulk Raj Anand. Ruth Prawer Jhabvala, who was her neighbor at the time, encouraged her literary pursuit. She soon found her material close by.

“That Old Delhi home and life was the one I knew best, the one I wrote about constantly,” Desai said. “After ‘Clear Light of Day,’ I became known as this woman writer who writes about a woman’s position in the family. I did it so often that I saw its limitations, and I wanted to open a door and step out of it.”

The book that opened that door was “In Custody” (1984), an elegy for the rarefied, male world of Urdu poetry that captured “the decline of a language, a literature and a culture,” Kalpana Raina, a Kashmiri-born writer and translator, said over email. It remains one of Desai’s most beloved works, and went on to become a successful Merchant-Ivory film in 1993.

Desai’s work expanded further in the years to come, with a string of novels — “Baumgartner’s Bombay” (1988), “Journey to Ithaca” (1995) and “Fasting, Feasting” (1999) — that featured an assortment of strangers in strange lands.

Desai herself had moved to the United States in the mid-1980s to teach writing at M.I.T. The harsh winters, among other things, were a shock to her system. As the snow piled up that first year, she booked an escape to Oaxaca, in Mexico, never expecting she’d return to the country often over the years.

“Getting to know Mexico opened up another world for me, another life,” she said. “It’s strange because it’s so like India, I feel utterly at home there. And yet there’s something about Mexico that’s surrealistic rather than realistic.”

“Rosarita” — like her 2004 novel “The Zigzag Way” — has been a way for Desai to reimagine Mexico in her fiction. When she came upon the story of the Punjabi artist Satish Gujral, who studied with Diego Rivera and other Mexican muralists, she began to envision a narrative that linked the “wounds, mutilations” of two violent historical events: Indian partition, which cleaved the subcontinent along religious lines in 1947, and the Mexican Revolution, a civil war that began in 1910.

Over time, she teased out the fragments of her tale, weaving in a mother-daughter story line as well — “the most familiar part,” she said. It was a mystery even to her, she admitted, where it would all lead. One thing she did know, though, was that it would be a novella, compressed and impressionistic. She had enjoyed writing her collection of novellas, “The Artist of Disappearance,” published in 2011, and the form suited her.

“It doesn’t take the immense energy and stamina that the novel requires,” she said. “You can finish it before it finishes you.”

While Desai claims this may be her last book, she is relishing the experience of watching her daughter Kiran continue the journey. Kiran’s debut, “Hullabaloo in the Guava Orchard,” appeared in 1998, just after India’s 50th anniversary. Her follow-up, “The Inheritance of Loss” — a masterwork that spanned Harlem and the Himalayas and awed her mother — won the 2006 Booker Prize. Rushdie has called the mother-daughter pair “the first dynasty of modern Indian fiction.”

Kiran is part of an impressive group of Indian novelists who emerged in the globalized 1990s, a far cry from the closed and isolated world her mother knew as a young writer in English decades earlier. “There has, of course, been a huge blossoming since that time and a more seamless connection between India and its diaspora authors,” Kiran explained over email. “I do think it is important to remember that it was lonely writers like my mother who opened the door for subsequent generations.”

Kiran calls her mother’s long writing life a “gift,” and isn’t so sure it’s done yet.

“She was born in British India and lived through such enormous changes,” added Kiran, who often works alongside her mother at her scenic home by the Hudson. “Now she always tells me she isn’t writing, but every time I pass her room I see her at her desk. Her days, at 87, are still entirely made of reading books, reading about books, and writing. It’s as if her whole life has been lived inside the world of art, every experience processed through this lens.”