I've started reading Philip Jenkins' new work, The Lost History of Christianity: The thousand year golden age of the church in the Middle east, Africa and Asia - and how it died (Harper One 2008).
Jenkins is the author of the seminal The Next Christendom: The Coming of Global Christianity(Oxford 2002) and a number of other well-written studies.
His new one does exactly what it says in the subtitle, namely chart the largely forgotten history of the church in the non European world from the first to the eleventh century.
In the introduction I was set thinking by this simple fact. in 1050 in Asia Minor - the cities of the seven churches of Revelation and the church planting exploits of Paul and his team - there were 373 bishoprics and virtually the entire population were Christian.
By 1450, barely 10 to 15% of the population were Christian and there were just three bishops.
This is a collapse of allegiance to the Christian faith that mirrors the experience of Europe over the past 400 years but which can't be accounted for by the rise of science and rationalism. Most would put it down to the rise of Islam but as Jenkins has already said, the church in the East lived fairly comfortably in Muslim states - contributing much to Islamic learning (see p18)
I look forward to reading Jenkins' interpretation of this extraordinary fact.