This study seeks to draw upon a wealth of recent specialised studies which focus on key issues relating to Spain during the civil war and the early years of the Second World War. It is the first general study of the significance of the Spanish area to the foreign policies and diplomatic relations of the Great Powers since the publication of Dante Puzzo's Spain and the Great Powers in 1962. Moreover, this book, by including Portugal and beginning from 1931, provides a more comprehensive account than hitherto achieved.