The fiction of R. A. Lafferty is at once deeply ecological and deeply strange. Its incessant narrative inclusion of the nonhuman beings, places, and forces of Lafferty’s Oklahoman and otherwise western bioregion evinces an imagination profoundly porous to the local specificities and abundance of one’s more-than-human context. In this way it is deeply ecological. Lafferty’s fiction is also known as one of the most uniquely off-kilter, wildly imaginative, and arcanely erudite bodies of work in U.S. literature. In this way it (...) is deeply strange. While it is often acknowledged that Lafferty transcends the genre of science fiction and that his work is sui generis, little has been done to place him as either a U.S. author generally or an author of regional place more specifically. This thesis attempts to initiate the placement of Lafferty as a bioregional writer of the Great Plains and Southwest, whilst placing equal emphasis on Lafferty’s literary mode as not so much science-fictional as weird, or monstrous. The fusion of these concerns leads this thesis to declare Lafferty a purveyor of American Weird Bioregionalism. Toward this end, we herein assemble insights from regional western U.S. narrative traditions together with recent ecocritical and ecophilosophical discourses to reconfigure contemporary Monsters Studies toward a more-than-human construal of monsters and the monstrous that reads Lafferty’s weird bioregional fiction through the lens of what this thesis terms an Ecomonstrous Poetics. A chapter devoted to an ecomonstrous reading of Cormac McCarthy’s southwestern novel Blood Meridian provides a canonical comparison to Lafferty with surprising overlap. A final chapter on Lafferty’s implicit ecotheology rounds out the thesis and opens it up to further research. (shrink)