For some time I have been wondering about the following cryptic reference which appeared in the Revenge of the Sith cross section book concerning the "Venator" proto-star destroyers:
These ships will see service for decades to come, as the Republic is transformed into the Empire. The Imperial Starfleet will justify its existence in unending war against separatist holdouts, dissident rebels and even, it is rumored, deterring barbarian invaders from outside the galaxy.
Here is the text as it appears in the book:
So here is my question: Who are these mysterious "barbarian invaders"? Is there something in the vast Star Wars universe to which this is probably referring, or is it an invention of the author?
I have tagged this question with "star wars legends" since the book was first published in 2005 and should probably be considered in that context.