Oak Brook – Ranking as one of the wealthiest communities in the United States, Oak Brook is home to incredible luxury and customized real estate that holds to the highest standards of architecture. The community has a relatively short history, becoming fully incorporated in 1958. The businessman and civic leader Paul Butler led the efforts to do so after opening up a dairy farm on the land currently known as Oak Brook, bringing the necessary commerce into the community to separate it from its neighbors in wealth and prestige.