In this lecture, I'll be providing the necessary background in ontology and epistemology to orient oneself in the field of assemblage theory as it originated in the work of Gilles Deleuze and Felix Guattari. After following the traces of monism and idealism through various presocratics, Descartes, and Hegel, I'll detail how Heidegger's work laid the groundwork for assemblage theory. After that, we'll be isolating a few passages from the third and fourth chapters, or "plateaus", of D&G's "A Thousand Plateaus" to locate the key reference points for establishing exactly what an assemblage is and how assemblage theory changes the way we view objects and their relationships to their environment. I'll be attempting to show how assemblage theory connects to physics, chemistry, micro/macrobiology, evolutionary theory, population studies, geopolitics, and much more to help get a handle on how to implement D&G's theory practically.