Does anyone know of any scholarly articles/papers that describe what the average congregational participation (vocal) at the liturgy was during the Middle Ages?
FWIW, you can start with Jungmann's now old sources (if you can read them in German and other non-English languages...) to see where the scholarship was in the middle of the 20th century. IIRC, Jungmann's general thrust is that congregational participation (not just liturgical but sacramental) in the West declined precipitously towards the end of Late Antiquity and in the early Middle Ages. This was followed by the period when the embryonic vernaculars were coming into development.
There's a video of congregational participation in the Middle Ages on youtube. That's how liturgists know so much about it. Oh, wait--how do they know, again?
For those of you who are in the South East of England (this board does appear to have an international readership), Canterbury Gregorian Society will host a relevant lecture on Saturday, 9th March. Helen Gittos, a History lecturer at the University of Kent, "will talk about the use of language in liturgy in mediaeval England. How much was in Latin and how much in English? We will explore the subject of what people actually said when they went to church and which parts of the services contained which languages." It isn't on the website yet, but I guess it won't be long before it is.
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