Livre d'Or

Oh cool, thanks so much for this thoughtful comment, Wych.

I found the very beginning a bit hard going
I didn't, I got into it almost immediately. But I generally don't have a problem with slow beginnings, to be fair.

but overall I loved it
*bounce* Isn't it just breathtaking?!

I felt the whole book was very *angry*
I think it was quite angry, but it managed to avoid letting the polemic swamp the story. The whole Cold War scenario, feeling that the whole of civilization was liable to be wiped out by politicians who didn't want to lose face, must have been quite angering. But there are far too many books that jump up and down clamouring 'nuclear war is bad', which, however true, doesn't make very interesting reading.

The Catholicism seemed mostly quite convincing to me, as well
And you'd be far more likely to see flaws in that than I would. Cool cool. I agree that Christianity is very often portrayed negatively in SF.

This was post-Roman Europe rather than the Conquest of the New World, you know?
Very acute comment! aCfL is definitely drawing parallels with the historical Dark Ages. But it's also true that Christianty is probably unjustly blamed for a lot of the sins of colonialism. The fact that most of the colonialists were Christian or nominally so I feel is only partly relevant.

I don't know if you've ever watched any Babylon 5
Nope, sadly. I saw a couple of episodes on TV years ago, and never really got into it. I'm very loyal to Star Trek; a lot of other stuff just seems like the same themes rehashed, but without the nostalgia value of crap special effects, meaningless technobabble, predictable plots and 60s sexism.