“The Empire” is the title the Earth Alliance (now Republic) gave to the other side of the war. The war which started in 2550 and has been ongoing since it recent pause in the year 3000.
The war from many points of view, was Earth winning and keeping the intruders out of the area. Those who were closer to the front, military or did some research shortly discovered that they were no winning the war, the other side was but they were moving slowly. Taking pieces of this Galaxy slowly in outlining sectors of space until they came up to the borders of Bohemian Sector and Gardenia Movement.
In the year 3000, the war suddenly stopped. The other side stopped shooting, giving the Earth Republic time and resources to rebuild to prepare for the next waves. The border is well patrolled on both sides, but the other side seems to only shoot back once attacked.