In the wake of a 1952 revolution, leaders of Bolivia's National Revolutionary Movement MNR embarked on a program of internal colonization known as the March to the East. In an impoverished country dependent on highland mining, the MNR sought to convert the nation's vast undeveloped Amazonian frontier into farmland, hoping to achieve food security, territorial integrity, and demographic balance. To do so, they encouraged hundreds of thousands of Indigenous Bolivians to relocate from the overcrowded Andes to the tropical lowlands, but also welcomed surprising transnational migrant streams, including horse-and-buggy Mennonites from Mexico and displaced Okinawans from across the Pacific.brbrBen Nobbs-Thiessen details the multifaceted results of these migrations on the environment of the South American interior. As he reveals, one of the migrants with the greatest impact was the soybean, which Bolivia embraced as a profitable cash crop while eschewing earlier goals of food security, creatin