The author defines Yesterday's Radicals as nineteenth-century Anglican Broad Churchmen and Unitarians, and aims in his book to demonstrate the affinities between them and the manners in which they influenced each other. The Broad Churchmen constituted the progressive wing of the Anglican Church, who were interested in science, Biblical criticism, a rational approach to religion, and who were leaders in the attempt to relate the Church's teaching to the new thoughts and conditions of the nineteenth century. But they were not alone. The Unitarians were possessed of a similar spirit, and came to regard reason and conscience as the criteria of belief and practice. This book demonstrates the growing respect between them, as they tried to grapple with the problems of their day. It lucidly takes the reader through the ramifications and complexities of Biblical criticism, and discusses the answers given to the problems of Biblical inspiration and miracles, amongst others. It demonstrates how Unitarians and Broad Churchmen affected each other, and that much of which is now taken for granted in enlightened theological circles was developed by Yesterday's Radicals. The author traverses territory not previously opened up in this way, for the affinity between these groups has hitherto not been the subject of analysis. This pioneering study was awarded the Earl Morse Wilbur Prize for Historical Research.