In the two loci classici about Roman satire, Quintilian and Diomedes famously draw a bifurcation of the history of the genre into two strands, which often comes in handy for modern scholars. This chapter argues that this bifurcation is the result of a stratification of, and compromise between, at least two different views: a communis opinio held by most authors of satire of the Republican period and their readers, and the single but ‘authoritative’ view of Horace, who established meter as a formal criterion to define satire. This chapter traces the origins of both views by discussing the relevant sources, and shows how Horace’s Satires appropriated pre-existing ideas about the nature and history of the genre, innovated on key aspects of them, and became a source of original ideas in turn. A similar scheme applies to Quintilian and Diomedes too: their perspective combines previous stances, but this combination itself represents an innovation which influences our own view of Roman satire in turn. Thus, while focusing on Roman satire, this chapter discusses a more general dynamic in the creation of literary histories.