Because the historical record makes reference to a substantial number of prosecutions driven by charges of impiety, including the notorious trial and execution of Socrates, a perception arose that there were continual attacks on freedom of expression in Athens in the half century that bracketed the Peloponnesian War. This was, however, also a time of intellectual, political, and social ferment, when ordinary citizens had reason to fear that traditional beliefs were being eroded and that the polis had incurred the displeasure of its gods. In this thesis, I examine how the interplay between this complex mix of factors and the malleable definition of the concept of impiety, as well as its emotive power, all facilitated the use, and abuse, of s...