This thesis studies ritual interactions between saints and the landscape, animals and elements during a three-hundred year period from 410 AD. Such interactions include negotiations about and with birds and other animals, exorcism of the sea, lakes and rivers, and immersion in these natural bodies of water for devotional purposes. Although writers of the period lacked a term such as 'nature' to describe this sphere of activity, it is demonstrated that the natural world was regarded as a dimension of creation distinctively responsive to Christian ritual. Systematic study of the context in which these rituals were performed finds close connection with missionary negotiations aimed at lay people. It further reveals that three British writers borrowed from Sulpicius Severus' accounts of eastern hermits, reworking older narratives to suggest that non-human aspects of creation were not only attracted to saints but were changed by and participated in Christian ritual and worship. Natural bodies of water attracted particularly intense interaction in the form of exorcism and bathing, sufficiently widely documented to indicate a number of discrete families of ritual were developed. In northern Britain, acute anxieties can be detected about the cultural and spiritual associations of open water, requiring missionary intervention to challenge pre-Christian narratives through biblical and liturgical resources, most notably baptism. Such a cosmological stretch appears to have informed a 'Celtic' deviation in baptismal practice that emphasised exorcism and bodily sacrifice. Nature rituals were a systematic response to the challenges of the British intellectual and physical landscapes, revealing the shape of an underlying missionary strategy based on mainstream patristic theology about the marred relationship between humans and the rest of creation. St Ambrose emerges as the most influential theologian at the time when the early church was shaping its British inculturation, most notably led by St Germanus' mission in 429.

Les bouleversements politiques et intellectuels provoqués par l’avènement du principat augustéen entraînent sous le Haut Empire une redéfinition des buts et des fonctions assignés à la formation intellectuelle de l’élite romaine et occidentale. Le développement de l’éloquence judiciaire et épidictique au détriment de l’éloquence politique modifie l’enseignement traditionnel de la rhétorique, tandis que la pratique philosophique prend de plus en plus de place au sein de la société et favorise le développement de son enseignement. Ces changements suscitent chez plusieurs auteurs des Ier et IIe siècles apr. J. C. des réflexions sur la manière d’améliorer l’enseignement rhétorique et philosophique alors que diverses initiatives sont prises pour organiser à l’échelle de l’Empire la diffusion de ces savoirs. Notre travail se propose d’examiner, en se concentrant sur les acteurs du système éducatif – professeurs et étudiants –, la façon dont cette formation intellectuelle se développe sous le Haut Empire dans les régions latinophones et de dresser une cartographie de l’enseignement de la rhétorique et de la philosophie en acquérant une connaissance concrète de ces personnages, par l’examen de leurs origines géographique et sociale et de leurs mobilités. Cette dimension réaliste se double d’une étude de la représentation de ces deux groupes dans la littérature impériale. Une attention particulière est portée à la question de la formation des futurs empereurs, dont la vie est richement documentée, afin de déterminer si la description de leur éducation est altérée par le souvenir qu’ils ont laissé de leur règne. / The political and intellectual upheavals caused by the advent of Augustus’ Principate result, in the Early Empire, in a new definition of the aims and functions assigned to the intellectual training of the Roman and Western elite. The development of judiciary and epidictic eloquence at the expense of political eloquence modifies traditional rhetorical teaching whereas philosophical learning is gaining importance within society thus favouring the teaching itself of philosophy. These changes bring several 100 and 200 A.D. authors to reflect upon the way of improving rhetorical and philosophical teaching. Meanwhile various initiatives are taken to spread these forms of knowledge throughout the Empire. By focusing on those who are in charge of the educational system – teachers and students – our research offers to examine how intellectual training develops in the Latin speaking regions in the Early Empire and to draw a map of rhetorical and philosophical teaching while getting to know these characters concretely through the study of their geographical and social backgrounds together with their mobility. Such realistic aspect goes with a survey of the representations of the two groups in imperial literature. Emphasis is laid in particular on the question of the education of the future emperors the documentation of whose lives is rich in order to examine whether the description of their education is altered by the memory that remains of their reign.