On a side note, what are the approximate frontiers of the Romulan Imperial State and the Romulan Star Empire? Do they occupy discrete territories, or are their worlds and systems mixed together?
Discrete territories. I didn't specify too much, partly to leave things open for future authors, but I basically viewed it (and Marco agreed with me) that it was split in half.
If you have Star Charts
, turn to pages 66-67. The Romulan Star Empire is egg-shaped in that representation. Draw a line from Nimbus to Dewa, and that's the approximate border, with the State above the line (which includes Achernar) and the Star Empire below it (which includes Romulus).