In 1971, Ryan took his firm public in order to finance his goal of diversifying the company’s offerings. He expanded by acquiring Globe Life and four insurance-brokerage businesses in 1976 and the James S. Kemper insurance agencies in 1981.

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But the following year came the watershed deal, when Ryan Insurance Group merged with Combined Insurance Co. of America and he took over as CEO from W. Clement Stone. Five years later, the new entity became known to Wall Street—and the rest of the financial world—as Aon (Gaelic for “oneness”).

Over the next two decades (Ryan served as CEO from 1982-2005), Aon acquired some well-known names in the insurance and consulting industries, among them the Benfield Group and Alexander & Alexander, in addition to such international players as Hudig-Langeveldt and Frank B. Hall.

The globalization of Aon, which Ryan notes “took place over a relatively short time,” is one of the professional achievements of which he’s most proud. He adds that he takes equal pride in the quality of Aon’s people.

Ryan’s other points of pride throughout his years at Aon’s helm are “the way we came through on some crises.”

One of the darkest days of his career—and the nation—occurred on Sept. 11, 2001 when 176 Aon employees were killed in the attacks on the World Trade Center. It wasn’t long after that Ryan decided medical benefits were to be extended to the immediate families of those employees whose lives were taken, and that their children’s tuition would be paid.

Another test of Aon’s fortitude came in 2004-2005 when Aon, along with other brokers including Willis and Marsh, found themselves under the microscope of then-N.Y. Attorney General Eliot Spitzer as well as attorneys general in Connecticut and Illinois over the practice of insurers’ contingent commissions to brokers.

In March 2005, Aon agreed to a $190 million settlement to be paid over 30 months to policyholders allegedly damaged by the company's actions.

Admitting no wrongdoing, Ryan said at that time in a statement that the company “now has these investigations behind us” and noted that “we do not agree with a number of allegations in the complaints.”

Ryan retired as chairman in 2008—but he couldn’t stay away from insurance for long. In 2010 he formed Ryan Specialty Group (RSG), a global organization designed to deliver specialty services to insurance agents, brokers and carriers alike.

After all he’s accomplished, how does an individual like Ryan want to be regarded? He pauses thoughtfully for several beats before answering the question.

“I’d like them to remember me as someone who if people needed help, that I’d be able to help them, whether personally related or professionally. That’s the bottom line for me.”