Answer:

ROMANEMPIRE

Answer	Crossword Clue
ROMANEMPIRE	Domain in the fall of 395
ROMANEMPIRE	Cicero's realm
ROMANEMPIRE	Historic realm.

ROMANEMPIRE	Part of H.R.E.
ROMANEMPIRE	Caesar was its prime moaner
ROMANEMPIRE	Edward Gibbon's subject
ROMANEMPIRE	It was established by Augustus
ROMANEMPIRE	Subject of a classic six-volume work by Edward Gibbon