Mr. Janklow was among the first of the so-called superagents, and became one by accident, stepping in to help with a book by a legal client and old friend, the speechwriter and columnist William Safire. Mr. Janklow was, credited, and faulted for the proliferation of blockbuster books and million-dollar deals in the 1970s and beyond, for jolting a gentleman’s trade with a lawyerly savvy about marketing, subsidiary rights and the fine print of a publishing contract.
He was a flamboyant character — so energetic he would dictate dozens of letters a day — a fighter on the tennis court and in the boardroom; a schmoozer with large-framed glasses and monogrammed white shirts; a whirlwind with a mental directory of one-liners, anecdotes and superlatives. Never afraid to cite his own accomplishments, Mr. Janklow liked to recall that some of the contracts he negotiated were worth more than the $25 million the Hearst Corporation needed to purchase the publisher William Morrow.
“One of the reasons to drive for big advances is not to make authors and agents rich,” Mr. Janklow told the New York Times in 1989. “It’s to make the publisher aware of what he’s bought. You’ve got to get them pregnant. They get up before their sales force and say, ‘We paid millions for this book. This is the biggest book we’ve got. Drive it into the stores.’ ”
He was at ease with liberals (Gore, Michael Moore) and conservatives (Reagan), with brand-name fiction writers such as Sidney Sheldon and Danielle Steel, and with the journalists like Ted Koppel and Daniel Schorr. His clout and credentials would multiply late in 1988 when he and fellow agent Lynn Nesbit announced the founding of Janklow & Nesbit Associates, with Nesbit bringing along such award-winning authors as Tom Wolfe and Robert Caro.
Not all his clients were superstars, at least at the beginning. He took on McCullough well before the historian’s million-selling “Truman.” He handled disgraced Nixon aid John Erhlichman, poet Diane Ackerman and the first novel by Jill Eisenstadt.
In recent years, Janklow & Nesbit authors included prize winners Joan Didion and Jhumpa Lahiri, along with the more checked James Frey, undone (under a different agency) as a memoirist but reborn as a novelist. Mr. Janklow’s son, Luke, negotiated deals for Anderson Cooper and Simon Cowell. Mort Janklow also had a daughter, Angela, a former editor for Vanity Fair.
Morton Lloyd Janklow, whose father was a lawyer, was born in Queens on May 30, 1930. He skipped enough grades to graduate from high school at 16. He graduated from Syracuse University in 1950 and Columbia Law School in 1953. His first marriage, to Marjorie Perrin, ended in divorce. In 1960, he married Linda LeRoy, daughter of Hollywood director Mervyn LeRoy, sister of restaurateur Warner LeRoy and his longtime partner in high society.
Mr. Janklow joined the law firm of Spear and Hill in 1960, and seven years later formed his own, Janklow & Traum. Among his clients was Safire, himself a former Syracuse student, who in the early 1970s was leaving his job as a speechwriter for President Richard M. Nixon and wanted Mr. Janklow to represent him for a memoir.
Mr. Janklow not only worked out a $250,000 deal with publisher William Morrow, but helped break publishing precedent by recovering around one-third of his advance when the publisher attempted to drop the book, claiming that the Watergate scandal made Safire’s story obsolete. (Authors usually had to return all the money.) Safire had left his job before Watergate emerged and his memoir, published by Doubleday, would be called “Before the Fall.”
“Bill ran around Washington telling all of his friends and colleagues about his friend who was his agent,” Mr. Janklow wrote in the Daily Beast in 2009, shortly after Safire’s death. “His opinion carried such weight even then that the telephone in my office began to ring … and within two years I abandoned a successful law practice and became an agent full time, a decision I’ve never regretted.”
In 1977, Mr. Janklow enriched Safire again when he negotiated a $1 million contract with Ballantine Books for Safire’s “Full Disclosure,” regarded at the time as the highest advance ever for a first novel. He would later negotiate seven-figure deals for “Silence of the Lambs” novelist Thomas Harris, and for memoirs by Reagan and Pope John Paul II, Ted Turner and Walters.
Mr. Janklow served on advisory boards, among them the Metropolitan Museum of Art, the New York Public Library and the Solomon R. Guggenheim Foundation. He was a member of the Council on Foreign Relations for over four decades.
According to the New York Times, he is survived by his wife and their two children; a sister; and six grandchildren.