The Oblique Ontological Terrain series developed out an oblique map atlas I found on-line published by the USGS in the 1970s. I redrew and enlarged sections of these maps by hand (pen and ink) while looking at them on my iPad. The word oblique means neither perpendicular nor parallel or not straightforward, indirect, obscure, devious or underhanded. Ontology is the half of metaphysics that studies the origins, history and essence of being. And, terrain means a geographic area or the physical features of a tract of land, but, also, a field of knowledge or interest. The definitions of the words in the title and the undulating mountains seemed to intersect perfectly with the isolation of Covid-19 lock-downs and tumultuous social upheaval of our time.