Boeotia was a nation which existed on Terra during the Age of Strife and the Unification Wars, chiefly known for its lengthy holdout stance to Unification and the eventual violent end to its sovereign status. It was held under the sway of King Kadmus.
An area of Terra mentioned in Imperial records as holding out against full Unification for some considerable time; while tacitly recognizing the Emperor's dominance, the ruling monarchy of Boeotia used all manner of diplomacy in order to avoid losing power. In a show of great patience and benevolence, the Emperor allowed the ruling family of Boeotia - the Yeselti - to carry on like this for over 150 years, with the intention that they would integrate themselves into unified Imperial Terra at their own speed and with as much dignity as possible. 
The Boeotian Conflict
Instead, the Yeselti clung onto their independence to the point where, firstly, the Imperial Army was forced to invade the province and finally, Legiones Astartes of the Thousand Sons were assigned to quash the truculent little state.
Trivia and Notes
- The nation of Boeotia draws its name from its real life Greek counterpart; several significant archaeological sites exist there.
- Boeotia was a battleground during the Greco-Persian Wars, when it was invaded by the armies of the Achaemenid Empire. The recruiting ground for the Astartes of the Thousand Sons is also known as the Achaemenid Empire and appears to effectively be the same place; thus, if Terran history is taken to mirror real world history by default, Boeotia has been invaded by warriors originating from the same place twice, but many, many millennia apart. If not, it remains a simple reference.
- The Great Crusade was said to have already begun when Boeotia was pacified; Space Marines already existed and the bulk of the Legions had previously left Terra to conquer the galaxy. The Boeotian Conflict currently holds the distinction of being a war of Unification that took place during the Great Crusade, the last and first currently known battle of each grand campaign respectively.
- 1: Prospero Burns (Novel) by Dan Abnett, Chapter One, pgs. 29-41
- 2: The Crimson King (Novel) - Chapter 18