Sagittarius Command by R. M. Meluch
Search for title: HCL RCL MPL SPPL MnLINK
Cool - I can't say enough about how fun these books are. It's a crazy idea (the whole Roman colonies versus USA dominated Earth) but I really like how she executes this.
After the finest battleship-class spaceship in Earth's fleet, the U.S.S. Merrimack, rescues a near-space Roman world besieged by a destructive alien life-form known as the Hive, the Romans' leader, Caesar Magnus, insists on honoring the ship's captain, John Farragut. But when Caesar is assassinated, Farragut must lead a mission into the heart of Hive territory in search of a Roman who has been presumed "dead" for decades.
