This paper offers a critical survey of scholarly studies of periodicals in the nineteenth and early twentieth centuries. Periodical publications dominated the production of literature and discourse in this period, both in America and in Britain and its colonies. This important area of long-nineteenth-century print culture, however, received scant scholarly attention until the mid-1960s. I will break down its development into three rough phases: the mid-1960s to 1970s; the 1980s and 90s; and 2000 to the present. The mid-1960s saw an urgent call for the establishment of archives of the nineteenth-century periodical, to further the historical and interdisciplinary study of literature in English. The 1970s witnessed the publication of important periodical directories. These included the invaluable Wellesley Index, which identified the legions of periodical authors who had published anonymously. The late 1980s witnessed a “theoretical turn” in archive-based periodical studies. Under the influences of Michel Foucault and Mikhail Bakhtin, the characteristics of authorship were redefined such that editors, publishers, and readers also came to be considered nodes of meaning-making that structured the discourse networks of the long-nineteenth century; and the polyphony of periodicals drew keener attention for what it revealed of conflicting social forces organized around gender, class, and race difference. At the turn of the new millennium, the global proliferation of digital media prompted a reappraisal of periodicals as a collective “genre” of print media, whose characteristic, periodical mode of production structured the rhythm of modern life. While recognizing the impetus and creative potential of the “media turn” in periodical studies, which assists in understanding the complexities of the mediation and remediation of texts, I criticize its tendency towards apolitical technologism. I propose a “thick reading” of periodical texts, relaunching the agenda of the “theoretical turn” of the 1980s, as an enriching parallel to the “thin reading” and “distant reading” that is more widely encouraged in periodical studies in the digital age.