Mark Eisner has been chasing Pablo Neruda for decades.

“It is a camino, a trail, a path,” Eisner says. “One thing has led to another and eventually to this book.”

Neruda: The Poet’s Calling is Eisner’s first biography, yet he paints a large, complicated picture that enhances our understanding of not only Neruda, but also large swaths of the 20th century’s political and cultural landscape. Eisner also includes his own translations of Neruda’s work and manages to balance literary analysis with deep historical detail.

Through academic study, the translation of The Selected Neruda: Essential Poems, the introduction to Jessica Powell's translation of Neruda’s rare venture of the infinite man, and now a magisterial biography, much of Eisner’s career has focused on Neruda. Yet it took a trip abroad for Eisner’s eyes to fully open.

“I always felt pulled to Latin America and [during college at the University of Michigan] studied in Central America,” Eisner says. “I’d read Neruda before, but now I’m reading it while working in the highlands of El Salvador. Anywhere you read Neruda you can get something, but there? Boom! That was my first real coming-to-Neruda moment.”

After more academic study and South American travel, including to Neruda’s Chile, Eisner began to feel a deeper connection to Neruda’s work and his world. Then, in 2003 he started Pablo Neruda! Presente!, a documentary about Neruda, narrated by Isabelle Allende.

While making the documentary, Eisner interviewed everyone from academics to Neruda’s close friends. But what really opened his eyes was seeing Neruda’s presence across the country. “I also interviewed people on the street, construction workers, people in the market, students. That was the time I really got to know the personal stories about Neruda but also the perception of him. He was so much in the culture.”

Eisner soon realized that Neruda couldn’t be understood as just another poet. He was too massive, too mythic, too important. Neruda’s influence extends from poets to political activists to pop stars like Taylor Swift, who claimed Neruda influenced her album “Red.”

“There’s three strands of Neruda: the personal story, the poetry, and also the politics and social activism. You can’t look at his life without looking at all three of those.”

Neruda: The Poet’s Calling balances each of these strands, and the clarity of Eisner’s prose keeps the reader from getting bogged down. The first few chapters, for example, paint a vivid and grim picture of the burgeoning Chilean railroad industry at the end of the 19th century. Far from being extraneous, this history, and Neruda’s first exposure to the exploitation of workers, is vital to understanding the man and his work.

“Each of the three strands is dependent on the others,” Eisner says. “It all works together and makes the vastness even more monumental. Neruda is always described as monumental, but if you put it all together it’s bigger—universal.”

After 12 years of writing, libraries of sources, and hours of interviews, Eisner still isn’t sure if his book does his subject justice. “When writing, you’re so much in a vacuum, but now that the book is out, people are starting to pick up on my argument. Did I get the point across? You don’t know until it’s out there.”

Ultimately, the explanation of Pablo Neruda’s significance is both simple and endlessly complex.

“In the end, it goes back to the universality,” Eisner says. “It’s really about his poetry and the wonder of being human, with all the fallacies, complexity, and greatness. It’s the central poetic expression of what we are at our core. That’s what keeps people coming back to him.”

Richard Z. Santos recently completed his first novel.