Roma Eterna — Robert Silverberg

No power on Earth can resist the might of Imperial Rome, so it has been and so it ever shall be. Through brute force, terror, and sheer indomitable will, her armies have enslaved a world. From the reign of Maximilianus the Great in A.U.C. 1203 onward through the ages -- into a new era of scientific advancement and astounding technologies -- countless upstarts and enemies arise, only to be ground into the dust beneath the merciless Roman bootheels. But one people who suffer and endure throughout the many centuries of oppressive rule dream of the glorious day that is coming -- when the heavens themselves will be opened to them...and the ships they are preparing in secret will carry them on their "Great Exodus" to the stars.