Presidential biographer Edmund Morris, best known for writing a book about the life of Ronald Reagan, has died. He was 78.

Morris died Friday in a hospital in Danbury, Connecticut, a day after suffering a stroke, his wife, Sylvia Jukes Morris, told The Associated Press on Monday.

“We at Random House mourn this loss with all who knew him and loved him, and with those who read his remarkable books. Our deepest sympathies are with his beloved wife Sylvia,” read a statement from Andy Ward, Morris’ editor.

Morris was a polished prose stylist whose career took off with the success of his first book, “The Rise of Theodore Roosevelt,” which won the Pulitzer Prize in 1980. But what cemented his legacy was “Dutch: A Memoir of Ronald Reagan.”

Aides to Reagan, who took office in 1981, thought Morris an ideal candidate for a book on him. Morris received a seven-figure contract from Random House and access most historians would only dream of: ongoing time with a sitting president, from meetings to private interviews, including with Reagan’s family.

“He had the guts to let somebody come in from outside, stare at him, read his mail, go off and talk to his children,? Morris said in 1991 . “Whatever you say about Ron Reagan, he has guts.”

But as Morris began work on the book, he realized that Reagan himself was a puzzle — an amiable man unknowable even to those closest to him.