When Brian Duperreault started as an actuary at AIG, he thought the firm’s name sounded so phoney it had to be a CIA front.

Today, AIG can be found in more than 80 countries, including Bermuda, and employs more than 25,200 people. But in 1973, AIG was not well known in the US.

In his newly released biography, Faith and Purpose: The Life & Vision of Insurance Industry Icon Brian Duperreault, he revealed that he was so unsure of his new employer that he cashed his first cheque immediately, worried that the company might disappear.

“Our claim to fame was more on the international side,” he told The Royal Gazette. “Hank Greenberg [then chairman and CEO] was in the process of building the US side. There was only a small group of people at AIG and I knew everyone in the company on the US side.”

Fresh out of the army, Mr Duperreault worked hard, but had a lot of fun. He quickly rose up the ranks, eventually running AIG’s international operations.

“We were doing things that others would not do, could not do, or should not do,” he said. “We were out there writing crazy risks and doing things like actually having relationships with the broker.”

In that age, most insurance firms did not like brokers, and preferred dealing with agents.

Today, Mr Duperreault is a titan of the insurance industry, having come to Bermuda in 1994 to transform Ace Ltd (now Chubb) into a reinsurance powerhouse.

In so doing, he also helped to turn Bermuda into a global insurance centre, and founded firms such as Hamilton Insurance Group, and this year cofounded Mereo Insurance.

In an interview with The Royal Gazette, Mr Duperreault described compiling the book with Wendy Davis Johnson as a “wonderful experience”.

“I was never a diarist,” Mr Duperreault said. “I never took notes during those times. I got the chance to think about all the things that have happened to me that I had completely forgotten or were deep in the recesses of my brain. These included my early days at AIG, which were wild.”

Ms Davis Johnson, the writer, had to track down old friends and do much research to put things together.

The biography details the insurance executive’s humble beginnings, raised by a single mother in Trenton, New Jersey. He often calls himself “Bermuda-born and New Jersey-bred”, another story documented in the new book.

In 1946, his mother, Peggy Duperreault, was elated when she found out she was pregnant, but her husband, Bill Duperreault, was less than keen.

Unknown to Peggy, her husband was a bigamist who had secretly married someone else after marrying her. He had three children with his other wife.

Only a few months into the pregnancy, Peggy found herself abandoned. Looking for support, she flew to Bermuda to be with friends who worked on the US Naval Air Base.

Brian Duperreault was born at King Edward VII Memorial Hospital in May 1947, and was baptised at St Theresa’s Church in Hamilton.

His mother’s intention was never to stay. When he was five months old, she moved them back to New Jersey.

He confessed that in school he was not terribly motivated.

“I played sports,” he said. “I love to compete. I went to college and got good grades, but frankly, I did not work that hard. I was there to get a diploma, and then a job.”

Time as a clerk in the army during the Vietnam War was the making of him.

Mr Duperreault confessed that he has never read Faith and Purposefrom cover to cover.

“I should read it,” he said. “It feels kind of weird to read a story about yourself.”

He had the book written for his four grandchildren, ranging from six years old to just a few months old.

“The time will come when they are old enough to read it,” he said. “By that time, hopefully, it will have a couple of more chapters.”