Jordan is exceptionally rich in churches for the most part dating after the 5th century, many being in the large cities but sometimes also in towns of lesser importance. The walls, but above all the pavements, with their rich mosaic decor, are often well conserved when protected by a covering of sand or earth. Over the last twenty years, an interest has also developed for the evolution of liturgical rites and therefore for the material installations which reveal their trace in places of worship. This book is divided into two parts. A continuous account examines successively the ecclesiastical organisation of the territory in the period under consideration, the repartition of the churches in the cities and in the countryside, the different types of plans and the resulting technical specificities (wood roofing, vaulted apses, and eventually domes), the mode of floor decoration in function of the plans, and sometimes the wall decoration, and also the liturgical furnishings (altar, ambo, seats) and installations (chancel, precincts, reliquaries) which are associated. Numerous synoptic tables and typological plates allow a rapid glance at the particularities provided by archaeology which, given the scarcity of literary sources, is essential for the history of the Churches in the provinces which correspond with Jordan at the present time, the hagiography in the region, the economic and social history, and the evolution in the liturgy. The inventory, interrupted in 1998, includes a normalised analysis of the architecture and liturgical furnishings of about 180 monuments. It reproduces and translates the numerous inscriptions (in general on mosaics) which allow quite precise dating of the churches between the 6th and the 8th centuries, sometimes the names of the titular saints and the circumstances of their construction or their decoration. The book is lavishly illustrated.