There were, of course, real churches in the Middle Ages: stone buildings with carved sculptures and stained glass, in which bishops governed, pre achers preached and the laity worshipped. These were hardly just ‘ideas’. But our ideas about ‘the Church’, or ‘the Medieval Church’ – what the sculptures and stained glass meant, how and why the bishops governed as they did, the impact of medieval sermons, and how the laity understood the church’s rituals – all of this comprises a construct, probably several constructs. Since we were not there at the time of the medieval church’s existence, this is perhaps the best we can hope for: an idea of what the past might have been like. Of course, we can insist that a good construct be based on the historical evidence, and that historians (and readers of history books) try to keep their biases in check. This is not always an easy thing to accomplish, as we can see if we look at past histories of the medieval church.