This is the first full-length study of one of the most prolific and controversial polemical authors of the seventeenth century. Newly available in paperback, it provides a detailed analysis of the ways in which Laudian and royalist polemical literature was created, tracing continuities and changes in a single corpus of writings from 1621 through to 1662. In the process, the author presents important new perspectives on the origins and development of Laudianism and ‘Anglicanism’ and on the tensions within royalist thought. Milton’s book is neither a conventional biography nor simply a study of printed works, but instead constructs an integrated account of Peter Heylyn’s career and writings in order to provide the key to understanding a profoundly polemical author. Throughout the book, Heylyn’s shifting views and fortunes prompt an important reassessment of the relative coherence and stability of royalism and Laudianism. Historians of early modern English politics and religion and literary scholars will find this book essential reading.