While John Nolen is best known as a city planner, he trained as a landscape architect at Harvard from 1903 until 1905 and continued to use the title ‘landscape architect’ even after he primarily adopted the title ‘city planner’. Nolen served as president of the National Conference on City Planning in 1926 and the first American president of the International Federation of Housing and Town Planning in 1931. He was also the chairman of the Committee on Parks and Public Reservations of the American Civic Association in 1909 and president of the Boston Society of Landscape Architects in 1932 and the Federated Societies on Planning Parks in 1933. Between 1905 and 1936 he was engaged in nearly 400 projects throughout the United States, from estate gardens to parks to new towns. While Nolen was an influential and prolific practitioner, his work has not been previously considered at length. The political and social foundations of Nolen's work can be found in his landscape design, overlooked in histories of city planning. In order to uncover Nolen's ideological grounding, I examine his writings, his personal letters and written works he referenced in the context of three projects central to his body of work—Madison (WI), Mariemont (OH), and Venice (FL). This dissertation shows how Nolen's work supported his vision of society with a clearly ordered civic realm kept distinct from a personal realm set in a naturalized environment. He organized these two realms at the metropolitan level based on the profitability of manufacturing interests. In addition, my analysis uncovers how Nolen used particular devices of landscape design to reinforce an ordering of society by class and race. The ways in which Nolen supported his vision of society with landscape design should make contemporary practitioners question both the ideological source and the political implications of the material strategies they employ in their own practice.