“In the following Sheets I presume to lay before the Public, an Essay, calculated for the use of those who wish to study musical composition, to teach music with propriety, or to judge of the music they hear, practise, and encourage.” So begins the Preface to Augustus Frederic Christopher Kollmann's An Essay on Musical Harmony, According to the Nature of That Science and the Principles of the Greatest Musical Authors (1796). And so begins mine. Kollmann's premise – that one's engagement with music is enhanced through attention to the mechanics of its construction – has withstood the test of time, even if what goes by the name “music” in Western culture by now has become so variegated that few essayists could presume to address it globally. I certainly am not so qualified or so disposed. Instead, I propose to focus my investigation of how harmonic analysis emerged as a field of musical endeavor principally on how musicians during the first half of the nineteenth century practiced it. My scope widens beyond that frame to accommodate eighteenth-century ideas that formed the foundation for developments after the turn of the century and to engage authors who refined existing approaches even as compositional and analytical practices headed in new directions later. Practitioners of a wide range of modern methodologies will find antecedents in abundance, though the authors I address did not regard their contributions as antecedent to anything: they were in the thick of things, co-participants in the musical culture defined by the composers whose works they scrutinized, and thus they felt themselves to be ideally qualified to make judgments and to propose productive modes of thought.