This paper reconstructs the origins of Gettier-style epistemology, highlighting the philosophical and methodological debates that led to its development in the 1960s. Though present-day epistemologists assume that the search for necessary and sufficient conditions for knowledge began with Gettier’s 1963 argument against the JTB-definition, I show that this research program can be traced back to British discussions about knowledge and analysis in the 1940s and 1950s. I discuss work of, among others, Bertrand Russell, G. E. Moore, A. J. Ayer, Norman (...) Malcom, and A. D. Woozley, showing how exchanges between different schools of analytic philosophy gave rise to new ideas about the nature of knowledge and analysis. Finally, I turn to Gettier's intellectual development and argue that his paper was influenced by some of these debates, suggesting that even his interpretation of Plato’s definition of knowledge can be traced back to discussions in this period. (shrink)