The Inquisition by Michael Baigent
This text presents a full history of the inquisition, beginning with St Dominic crossing the Pyrenees into Spain and the persecution of the villagers of South-West France that followed, right through to the holy index of forbidden books in the 20th century. The book gives a full account of how the church has as tried to ring-fence its beliefs over the centuries - from full-scale violent persecution to the more subtle censorships of recent years.