This study examines, within a chronological framework, the major themes and personalities which influenced the outbreak of a number of Evangelical clerical and lay secessions from the Church of England and Ireland during the first half of the nineteenth century. Though the number of secessions was relatively small-between a hundred and two hundred of the ‘Gospel clergy’ abandoned the Church during this period-their influence was considerable, especially in highlighting in embarrassing fashion the tensions between the evangelical conversionist imperative and the principles of a national religious establishment. Moreover, through much of this period there remained, just beneath the surface, the potential threat of a large Evangelical disruption similar to that which occurred in Scotland in 1843. Consequently, these secessions provoked great consternation within the Church and within Evangelicalism itself, they contributed to the outbreak of millennia! Speculation following the ‘constitutional revolution’ of 1828-32, they led to the formation of several new denominations, and they sparked off a major Church-State crisis over the legal right of a clergyman to secede and begin a new ministry within Protestant Dissent.