My dissertation, "Creating an Indian Ocean Rim Ecosystem: Forestry, Science, and the British Empire 1864-1963," argues that foresters and botanists in British colonies around the Indian Ocean rim attempted to coordinate scientific forestry policies, introduce and grow similar trees, and, ultimately, create a new ecosystem spanning the entire Ocean rim. This period corresponds to the creation and then fragmentation of an Indian Ocean network of foresters, beginning with the founding of the Indian Forest Service in 1864 and ending with the decolonization of British East Africa in the early 1960s. During this period, foresters and botanists planted millions of teak, rubber, pine, eucalyptus, palm, sisal, cinchona, and gutta percha trees in cities, plantations, and the countryside of colonies along the Indian Ocean rim. By using the Indian Ocean rim as my geographic focus, I contest Alfred Crosby and Jared Diamond's famous argument that Old World plants were more successful than New World and Australasian plants at flourishing in foreign environments by showing the success of New World and Australasian trees in the Old World, such as Australian eucalyptus in Africa and Asia and Brazilian rubber and Peruvian cinchona in Malaya. I argue that the movement of various species of trees around the Indian Ocean during British imperialism was deliberately intended to construct a specific ecology to suit scientific and economic demands of British imperialists. While I look at this Indian Ocean ecosystem as a socially constructed process, I do not disregard the influence of nature on the spread and growth of trees. My dissertation uses methods from history, geography, and ecology to describe the environmental constraints leading to the social construction of a new Indian Ocean ecosystem. In short, I seek to reconcile social history with ecological history while offering my own new interpretation of the environmental impact of British imperialism.