It has been 70 years since, humanity had mastered the travel of speed of light and light-year, and FTL Travel. Along with that, humanity has made fleets of spaceships after few more years and shit ton of tests, fails but it was success. Little thing, you and rest of humanity knows. That humanity was going into Galaxy war with the Galactic Dominion (Not from star wars), and their shit tons of allies aliens.

But that was 15 years ago now, it is currently year: 3045. As it been 30 years since the war between the The Galactic Dominion and Humanity. And right now with you, an commander of the largest fleet. That earth made and you're standing in the bridge looking out at space.