Simon's life encapsulated an era. In the 1950's, when he began his career as a developer, the shopping mall was in its infancy. Open-air shopping plazas had existed since ancient times, but postwar suburban development inspired large retail centers, leading to enclosed shopping behemoths. When Minnesota's 95-acre Southdale Center Mall opened in 1956, it was the country's first fully enclosed climate-controlled shopping center. (Simon later bought that property.)
At roughly the same time, Simon began his career as a leasing agent for Indianapolis's Eastgate Shopping Center, an open-air mall which he later bought in the 1980s. Simon founded Melvin Simon and Associates with his brother Herb in 1960 and began by building outdoor strip malls. Soon, the firm expanded into the huge enclosed temples to commerce that gradually came to dominate the American shopping landscape.
By 1967, Simon owned more than three million square feet of retail property. Over the next decades, the company added more than a million square feet per year. In the 1980s, the Simons were opening three enclosed malls in the U.S. every year.
In the process, Simon also helped develop the concept of the anchor store. By building relationships with big department stores like Sears and JCPenney, he laid the groundwork for the marketing balance of today's malls, with huge tenants providing the structure for smaller boutiques. He also built the country's largest mall -- the Mall of America, in Bloomington, Minnesota -- in 1992.
In 1993, the Simons went public, naming their company the Simon Property Group. They raised $1 billion in what was then the largest real estate offering in history. Today SPG controls approximately 244 million square feet of retail property space.