Forty years after Charlemagne’s imperial coronation, Walahfrid Strabo, thirty-three-year-old abbot of the monastery of Reichenau, wrote a history of mid-ninth-century Frankish liturgy: Libellas de exordiis et incrementis quarundam in observationibus ecclesiasticis rerum—A Little Book about the Origins and Development of Certain Aspects of the Liturgy. It was the first account of liturgical development, and the topics ranged widely over thirty-two chapters, from bells to baptism, language to litany. Most of the subjects were in a state of change or expansion. Where there was controversy—for example, should a priest celebrate the Eucharist more than once a day—the history of a practice would help to underline the essential elements and to demonstrate the Christian constants as opposed to cultural diversity. Where there was development, such as the increasing number of hymns available for the Liturgy of the Hours, the history of that practice was appropriate and timely.