RICHARD SERMON is a graduate of the Dorset Institute of Higher Education (now Bournemouth University) and the University of Southampton, with almost forty years' professional engagement in British field archaeology and heritage protection. His formal career began at the Museum of London where as a senior archaeologist he supervised excavations in the historic City of London and in 1990 correctly identified the Gresham Street medieval mikveh (Jewish ritual bath). He went on to hold senior positions as deputy director of the Scottish Urban Archaeological Trust, and following a move into local government, as city archaeologist for Gloucester and finally as county archaeologist for Bath and North East Somerset. He has related interests in musicology, linguistics, and folklore, having written on various subjects ranging from medieval bone flutes and the origins of the pipe and tabor, to the philology of wassailing and the use of folkloric motifs in the 1973 cult horror film The Wicker Man (Luath Press 2006). His work has been published in Bristol & Avon Archaeology, Current Archaeology, Decies, Folklore, Glevensis, Jewish Historical Studies, Northern History, Oxoniensia, Time & Mind, and the Proceedings of the Society of Antiquaries of Scotland, along with other periodicals and journals. In this volume he returns to the subject of early calendars and festivals in Britain and Ireland, pulling together much of his earlier work and introducing a wide range of new or previously under-researched material.