Deeply influenced by emotional, ethical, and ecological principles, John Steinbeck developed a holistic ideology to describe and analyze the relationships among individuals, society, and the more-than-human world. Although he explored environmental issues with ecological insight and philosophical contemplation that placed him well beyond his literary and scientific contemporaries, Steinbeck’s contributions to modern ecological inquiry and environmental thought have received only intermittent attention from literary scholars. Throughout his writing, Steinbeck develops a view of intellectual holism that encourages (perhaps even enables) us to dovetail science and ethics as we attempt to construct a new environmental paradigm. Viewing the world through his holistic lens, Steinbeck was able to see the global ecosystem, local environments, human communities, and even minute tide pools as objects of scientific and artistic inquiry. Specifically, it is my contention that the American environmental movement owes a greater debt to John Steinbeck than it realizes. In short, John Steinbeck made significant contributions to the growing awareness of human-nature interconnectedness and the parallels between social ills and ecological ailments. Yet, for whatever reasons Steinbeck is not granted a position of honor alongside the other giants of American environmental thought. Now witnessing the full blossoming of 21st century environmentalism, it is useful to cast a reflexive eye upon our ideological forebears with the intent to better understand the genealogy of the American environmental movement. Doing so will not only provide a richer and fuller family tree, but will also promote additional flourishing of new approaches to solving ongoing environmental troubles.