Robert Silverberg paints an alternate history in which the Roman Empire survives to this day. He sketches the last 2000 years of alternate history with a series of episodes each set in a critical time for the Empire.
I enjoyed this a lot, each of the mini-stories is stories is worth reading in its own right and they are well stitched together. If you read this looking for Roman themed entertainment with a twist you will not be disappointed. You will however be disappointed if you expect a serious attempt at alternate history. There are no great insights or intuitive leaps here. Instead of seriously trying to imagine what could have happened Silverberg has simply taken actual historical events as we know them and patched them into a Roman story. Events like the renaissance and the industrial revolution happen pretty much on schedule which is a bit unimaginative. If Europe had not collapsed in to the Dark ages after the fall of Rome would it really have taken that long to discover the printing press?