Malevil - French Author:Robert Merle Un guerre atomique devaste la planete, et dans la France detruite un groupe de survivants s'organise en communaute sedertaie derriere les remparts d'une forteresse.
While parts are a bit dated, and other parts are sort of hard to believe (i.e. radiation doesn't kill them) its a great story, interesting characters and enjoyable tale of life after the bombs drop and major cities are wiped out.
The owner of a castle has friends come stay with him and they at first try and survive, then later try and rebuild, uniting people and fighting a dictator. Along the way they struggle to keep livestock alive, plant crops in 'nuclear winter', etc.
I've read A LOT of PA books and this was one of my favorites.