The aftermath of the Popish Plot and the subsequent succession crisis of the years 1678 to 1681 are the context for this new study. It asks two key questions: was there an exclusion crisis? and did these years witness the birth of modern political parties? The author argues that the unrest was not simply due to a centrally organized party machine based around the single issue of exclusion; but was a broad-based controversy about the succession, fears of popery and arbitrary government which produced ideological polarization and political sophistication. Part One examines central politics to explore the succession crisis within the context of the court and an emergent political structure. Part Two explores public opinion in the country as a whole, and argues that propaganda electioneering, religious conflict and petitions committed men to organized networks of belief.