A History of Christianity is a six-part British television series originally broadcast on BBC Four in 2009. The series was presented by Diarmaid MacCulloch, Professor of History of the Church at St Cross College Oxford, and considers the evolution of the Christian faith and its four main forms: Orthodoxy, Oriental Christianity, Western Catholicism and Protestantism.Hat Tip Atheist Media Blog
Episode 2: Catholicism - The Unpredictable Rise of Rome
Episode 3: Orthodoxy - From Empire to Empire
Episode 4: Reformation - The Individual Before God
Episode 5: Protestantism - The Evangelical Explosion
Episode 6: God in the Dock
This is pretty fascinating stuff.
Diarmaid MacCulloch is the author of the massive 1216 paged book, Christianity: The First Three Thousand Years.