David Iannucci still remembers looking up at Milt Peterson, standing on a strip of dirt in front of a large crowd, telling people he was crazy.”

He was so self-effacing, we saw him as a visionary and he just responded with a joke that he was crazy to be building in the recession,” Iannucci, CEO of Prince George’s County Economic Development Corp., said of the day the renowned developer promised that that stretch of dirt would rise to become the $4 billion National Harbor project.

Peterson, founder of Peterson Cos., died Wednesday at 85. Reaction poured in from business and political leaders around the nation, including from many executives Peterson had worked with in the years since he founded his company in 1965 and took on projects like Fair Lakes, Burke Centre, downtown Silver Spring and National Harbor, a 300-acre mixed-use mini-city rising where decades of other ideas had fallen short.

“An influential pioneer in the Washington, D.C. real estate market and dedicated philanthropist, Milt’s legacy will live for years to come,” Hitt Contracting tweeted.

Iannucci and others recalled Peterson as earnest with a self-deprecating sense of humor and a determination not to be “unhumble.” In interviews, which he rarely gave, especially in recent years, the developer spoke in a steady, thoughtful cadence and deflected attention away from himself.

But his influence, especially with the developments in Greater Washington, is unquestionable.

“I had so many wonderful conversations with him, and his enthusiasm and vision for National Harbor was absolutely contagious among Prince Georgians,” Prince George’s County Executive Angela Alsobrooks tweeted. “He was truly one of a kind and a great friend to Prince George’s County.”

Maryland Gov. Larry Hogan tweeted sympathies to Peterson’s family — he is survived by his wife of 64 years, Carolyn, and a huge extended family — and lauded his work with downtown Silver Spring, developed by Peterson and Foulger-Pratt. MGM Resorts International CEO Bill Hornbuckle, who worked with him to develop MGM National Harbor, offered his own memories.

“Milt was not only a development pioneer and business leader, he was a friend, humanitarian, and beloved husband and father,” Hornbuckle tweeted. “His vision and leadership helped transform Prince George’s County, the capital region and beyond and will have a lasting impact on the community at large for many years to come.”

The Northern Virginia Chamber of Commerce said in a statement that he “led an industry with vision and creativity,” while Monumental Sports & Entertainment CEO Ted Leonsis said Peterson “helped to design and build our entire extended D.C. community – brick by brick.”

He was also remembered by George Mason University, where a $10 million gift from Peterson’s family helped to build the Peterson Family Health Sciences Hall. The Peterson Family Foundation has invested more than $100 million in myriad causes since its founding in 1997.

“We are deeply saddened to hear of the passing of Milt Peterson, a generous benefactor and friend of [George Mason University], and a namesake of the Peterson Health Sciences Hall,” tweeted GMU President Gregory Washington. “Our condolences go out to Carolyn and the entire Peterson family.”