Mazie St. John is on top of the world.

The attractive, energetic widow, who divides her time between Weekapaug’s Haversham and Florida’s Jupiter Island, has accomplished a major life goal.

She has just published the biography of her late husband, “Legend & Legacy: The Life of Seymour St. John,” a project nearly 20 years in the making.

“This is thrilling,” said St. John, with a mixture of wonder and élan. “Seymour’s story just had to be told.” Marie Race and Seymour St. John were married on June 24, 1989, in the Weekapaug Chapel. It was a second marriage for both.

“I had been married to my first husband for 38 years,” said St. John, who had four grown children and a number of grandchildren when she and Seymour met in 1987.

“I couldn’t believe I could fall in love again,” she said. “But I fell in love with Seymour.”

“I’ve been so blessed,” said St. John recently, as she discussed her life, her adventures with Seymour, and the process of publishing the book. “Seymour was truly a legend.”

“I felt so sincerely that Seymour led a truly remarkable life,” she added. “He was so admired and so respected and well-known that a book had to be written.”

Marie Race was still mourning the loss of her husband, Scott, when she met Seymour St. John.

A mutual friend, Louise Walsh, introduced them in Florida during the spring of 1987. Walsh dropped a note to Seymour, who was on Jupiter Island, letting him know that her house guest enjoyed tennis as much as he and suggesting that Marie might be available to play, if he needed a fourth.

“You should call and invite “Marie” to play,” Walsh suggested. Seymour, mistaking the “r” for a “z” in “Marie,” called and asked, “When does Mazie arrive?”

“I’ve been Mazie ever since,” smiled St. John. “I define my life in ‘Before Seymour as Marie’ and ‘After Seymour as Mazie.’”

St. John, the former Marie Race, grew up in Hartford, the daughter of a prominent West Hartford surgeon. During her 38- year marriage to Race, a successful printing executive, she raised four children — Rick, Lolly, Meg and Marie, Jr. — and established a thriving interior decorating business. She is also an artist, a painter whose cheerful paintings adorn the walls of her Haversham home.

“Legend & Legacy: The Life of Seymour St. John,” she says, “chronicles the life of a great American educator, cleric and intellect.” The project began soon after their marriage, when the newlyweds were in the attic of the St. John family summer home in Haversham.

“The attic was in complete disarray,” she recalled. “There were cartons and cardboard boxes filled with papers everywhere and more papers all over the floor.”

After her initial surprise, she learned that the scattered papers were actually important pieces of history and included letters, sermons and speeches from the past seven decades of her new husband’s fascinating life, and she felt an instant need to have them organized.

“As I learned more about Seymour’s career and life experiences,” she continued, “and about what a fascinating life it was, I knew I wanted his biography written.”

The Rev. St. John served as the headmaster of the prestigious Choate School, a prep school in Wallingford, Conn., a position held previously by his father, George St. John. After graduating from Yale, St. John returned to Choate to teach French and German and coach athletics. He left to enter the Episcopal Theological Seminary in Alexandria, Va., where he was ordained in 1942. During World War II, he served in Europe as a lieutenant commander in the Naval Reserve.

As headmaster, he traveled extensively, visiting private schools around the world. His circle of friends included Eleanor Roosevelt, John F. Kennedy, Douglas Dillon and Edward Albee. St. John’s first wife, the former Margaret Spencer, to whom he was married for 50 years, died in 1986. St. John died two years ago at the age of 94.

Originally, said St. John, she wanted to tackle the project by herself. She had already written two small books about her husband — “In Pursuit of Seymour,” the tale of their courtship, and “An Adventure with Seymour,” an account of her husband’s reunion in France with wartime friends. But when she learned about a firm called Back to Back, a service company created to “do anything you don’t want to do yourself,” she and her husband hired them to help.

Six months later the Back to Back husband and wife team had sorted through the papers, catalogued them and organized them into 19 large plastic bins.

But when St. John looked at the number of paper-filled bins to be studied and documented, she realized it was too daunting a task for her to tackle alone. She connected with a writer from Wickford, Edward Renehan Jr., author of “Lion’s Pride,” a biography of Theodore Roosevelt, and “The Kennedys at War,” about the war years of another Choate alumnus, President John F. Kennedy.

She and her husband invited Renehan to Haversham for lunch one day because it was very important to her that the author meet her late husband and have the opportunity to experience firsthand his “sweetness and sense of humor.” That day, the book began to take shape.

“Seymour was a love of a man,” said St. John. “He always had a twinkle in his eye, and such an incredible following.”

“She’s very excited about this project,” said Sam Cofone, former owner of Sandy’s Fine Food Emporium, who has known St. John for that past 18 years and the St. John family for generations. “They were a very good match,” Cofone said of Seymour and Mazie. “She is quite the lady and he was quite the gentleman, and both very learned.”

Mazie St. John’s late husband used to preach at both the Watch Hill and Weekapaug chapels during the summer months, she said, and when he did, both chapels would be packed.

One of her most cherished memories of their years together was when Seymour would conduct the Blessing of the Fleet ceremonies at the Weekapaug Yacht Club.

“It was always such a lovely ceremony,” she recalled, describing how little sailboats full of children dotted the pond. “He would bless the boats and look toward the sky.”

“He had a way of connecting the children,” she added, “with the one who made the wind.”