"It is impossible to exaggerate the importance of Jansenism as a religious phenomenon in European life, and yet during the seventeenth century its followers denied its very existence. Jansenism, and the theology of Cornelius Jansen, powerfully infused French political life from the mid-seventeenth century to the Revolution 150 years later. It influenced the Enlightenment, the development of French constitutional thinking, the destruction of the Jesuits, and the modernisation of the Catholic Church." "Professor Doyle has written a book that is invaluable for students of European history. It explains exactly why Jansenism was so important, recreates the religious and intellectual world which fostered it, and examines the critical issues, such as the all-pervasive role of the Jesuits in Catholic life and the importance of the movement in sowing the seeds of resistance to absolute monarchy, which led up to the French Revolution."--Jacket.