The term “fan,” in the human sense, didn’t come into common use until the 1890s. Obviously, before that time, people were passionate about art, sports, and performance. Instead of “fans,” however, they were amateurs, beggars, boomers, buffs, bugs, connoisseurs, devotees, dilettantes, enthusiasts, fanatics, the fancy, fiends, gluttons, habitués, heads, hounds, kranks, lions, longhairs, lovers, maniacs, matinee girls, nuts, rooters, and more. (Wagner had his very own Wagnerians). All of these terms require contextual understanding, of course. Many of them, for instance, originally had derogatory connotations meant to codify and control audiences through public discourse. But surveying such names at least offers one a provocative entry point into fandom’s history.
I have long used etymologies in various dictionaries to follow the trail of some of these words. Another way to go about word research is to use Google Books, where you can do searches for terms from among millions of digitized historical texts. Such searches do not distinguish between multiple definitions and can be deceivingly inaccurate, but they still point to resources that might not surface otherwise. A new application that visualizes such searching is the Books Ngram Viewer, which is based on the work of folks at the Cultural Observatory at Harvard University. It can do cool things like compare the chronological occurrence of the term “music lover” versus “krank” (from baseball) in the Google Books database. Of course, there’s nothing here that tells you about the changing definitions of such terms, or the actual experiences of the people involved; that’s the hard part.