Born in Granville, New York, Whitaker became enthralled with stories as a boy. His family struggled with poverty. He lived for several years in Albany, New York as a youth (a time portrayed in his last published work).

Whitaker earned bachelor's and master's degrees at the University of Washington. While there he wrote and directed his three-act play Eve of the Bursting. Whitaker went on to earn a doctorate in communications and film at Northwestern University.

He taught at Dana College in Blair, Nebraska, where he was chairman of the communications division. He served in the US Navy during the Korean War. Later he was awarded a Fullbright scholarship for study in England.

When Whitaker wrote his first two novels, he was chairman of the Department of Radio, TV and Film at the University of Texas, Austin, where he continued to teach for many years.

Whitaker married the former Diane Brandon, and they had four children: sons Lance and Christian, and daughters Alexandra and Tomasin. They lived for years in the Basque countryside of France.

Whitaker died December 14, 2005 in the English West Country. He was survived by his wife and grown children.

Whitaker said his wife chose the pen name Trevanian based on her appreciation of English historian G.M. Trevelyan. Trevanian wrote many bestselling novels in different genres, which received highly favorable critical reviews.

His first novel, published at the age of forty when he was teaching at the University of Texas, was The Eiger Sanction, an intelligent, gritty and thrilling spy spoof. It became a worldwide best seller. In 1975 it was adapted as a movie directed by and starring Clint Eastwood. Trevanian described the movie as "vapid" in a footnote in his later novel Shibumi. He requested (and received) a screenwriting credit as Rod Whitaker. The balance of the script was written by Warren Murphy, the mystery writer perhaps best known for co-writing the Destroyer series of men's action novels.

Saddened that some critics did not 'get' the spoof, Trevanian followed it with an even more intense spoof, The Loo Sanction (1973), which depicted an ingenious art theft (which was copied by thieves in Turin). Then came The Main (1976), a roman policier set in a poor neighborhood of Montreal with Claude LaPointe, a police lieutenant in his mid-50s whose wife had died young, as the lead character. Trevanian originally intended to publish The Main under the pen name Jean-Paul Morin.

Next came Shibumi in 1979, Trevanian's meta-spy novel, which received the most critical acclaim. In 1983 he published The Summer of Katya, a psychological horror novel. The widely diverse books solidified the myth that "Trevanian" was a collective pen name for a group of writers working together. Under the name Nicolas Seare, Trevanian also published 1339 or So: Being an Apology for a Pedlar (1975), a witty medieval tale of love and courage; and Rude Tales and Glorious (1983), a bawdy re-telling of Arthurian tales.

After a 15-year absence from domestic publishing, in 1998 Trevanian reappeared as the author of a Western novel called Incident at Twenty-Mile, and a collection of short storiestitles Hot Night in the City (2000). His last novel, written while he was in declining health, took a surprising turn.

The Crazyladies of Pearl Street (2005) depicted the coming-of-age story of Jean-Luc LaPointe, a boy surviving with his mother and sister in the slums of Albany, New York in the years preceding and during World War II. Although the book was published as fiction, commentators described it as autobiographical. In November 2005 it was selected as one of eleven Editors' Choice books by the Historical Novel Society.

In the summer of 2005, Crown Publishers relaunched a trade paperback set of five of Trevanian's earlier books: The Eiger Sanction, The Loo Sanction, The Main, The Summer of Katya and Shibumi.

Street of the Four Winds, Trevanian's tale of Parisian artists caught in the 1848 revolution, based on his meticulous research of the era, remains unpublished. An excerpt is posted on Trevanian's web site.

Whitaker kept his true identity unknown for years. He refused to grant interviews or contribute to the publicity efforts of his publishers. His first known interview was granted to Carol Lawson of The New York Times for a June 10, 1979 article coinciding with the release of Shibumi. In this article Trevanian stated that "Trevanian is going out of business. Now he can talk."

It was rumored that Trevanian was Robert Ludlum writing under a pen name. Trevanian rejected that idea stating, "I don't even know who he is. I read Proust, but not much else written in the 20th century."

Trevanian wrote successfully in every genre. In a 1998 interview with Newsweek, he said that with each new book, he first decided what author should tell the story. He used Method-acting techniques to imagine himself as the author in order to work into the story he wanted to tell. Trevanian fans followed his style changes with delight.

Trevanian said of his fans:

"The Trevanian Buff is a strange and wonderful creature: an outsider, a natural elitist, not so much a cynic as an idealist mugged by reality, not just one of those who march to a different drummer, but the solo drummer in a parade of one."

This was another poke at the masses...most notably the United States and Americans in general...since his apparent disillusion with the country led him to abandon it. In later years Trevanian was more outspoken about the reasons surrounding his voluntary exile from the country of his birth; he cited America's material obsession was one of the main reasons behind the declining quality of life in the U.S. He said that one day Americans would wake up and realize that cheaper is not necessarily better. Trevanian also addressed the issue of value on his website.

As Trevanian

• The Eiger Sanction (1972)
• The Loo Sanction (1973)
• The Main (1976)
• Shibumi (1979)
• The Summer of Katya (1983)
• Incident at Twenty-Mile (1998)
• Hot Night in the City (2000)
• The Crazyladies of Pearl Street (2005)

As Nicholas Seare

• 1339 or So ...Being An Apology for A Pedlar (1975) (1339 or So... was, in early form, a stage play titled Eve of the Bursting)
• Rude Tales And Glorious (1983)