I think the chart says it all really… I’ve totalled up the number of points scored by books with authors from each country. Since the lists considered almost exclusively those books which were either written in English or have been translated into English and widely read, it was obvious that the UK and USA would dominate, just a question of which. The other day Jo commented that the list is heavy on 18th and 19th century classics; having read back through it, it did surprise me a bit how many there were; I had remembered it having more of a 20th century flavour. So the UK is certainly helped by the traditional focus of the list. Russia does surprisingly badly – but it’s only really represented by two authors (I took Nabokov out of this because I couldn’t decide whether he belonged to Russia or the USA. He should probably be awarded to Russia really, which would at least put it comfortably ahead of Ireland…).
N.B. this is based on the top 200 books overall. I think I mentioned that I had about 750 books in the database; I’m using the top 200 because they’re the ones I have the best data on (e.g. country, date of publication, etc).