The music of early medieval Latin song has hitherto been known to only a handful of specialists. Notations survive in manuscripts from ecclesiastical centres across the Frankish kingdoms from the ninth century through to approximately the end of the eleventh, but the fragmentary written record has relegated wider appreciation to the occasional cum neumis found in the footnotes of the volumes of Monumenta Germaniae Historica and Analecta hymnica medii aevi. The difficulties involved in reconstructing melodies from mnemonic notations have also tended to obscure a body of song made up of hundreds of accentual verses (rhythmi), metrical verses by medieval authors from Eugenius III of Toledo through to Alberic of Monte Cassino, settings of late antique poetry by writers such as Boethius, Prudentius and Capella, extracts from classical authors (most notably Vergil and Horace) and computus. One of the purposes of this paper will be to outline the full extent of this song tradition, examining hints about uses and users that survive in manuscripts associated for the most part with large abbeys and cathedrals. A second aim will be to examine prevailing models of song transmission, challenging universal theories proposed for rhythmi in particular by Karl Strecker and Dag Norberg, emphasising instead genealogies specific to individual songs and the role played by a number of different centres in shaping the tradition. A third aim will be to explore the limits of reconstruction, seeking in the absence of full information about melodic contents to establish how much can be recovered from the various types notational strategies adopted, and how much can be identified about modes of setting associated with particular verse forms. In seeking to summarize various aspects of what appears to have been a continuous song tradition strectching from novices through to notaries, abbots, bishops, and even Kings, it will finally be suggested that the early medieval Latin song tradition forms a significant precusor to the later flowering of vernacular song in medieval courts.