Second Great and Bountiful Human Empire

The Second Great and Bountiful Human Empire was a political entity with influence in three galaxies. By the 42nd century, it had spread from an overcrowded Earth throughout the galaxy known as Mutter's Spiral and two others, including the Andromeda Galaxy (one can reasonably infer the other is the Triangulum Galaxy, the next closest galaxy after Andromeda). These three galaxies were collectively referred to as the Tri-Galactic. The currency of the Empire was the credit. The Empire commonly used Ood as slaves. (TV: Planet of the Ood)

One of the farthest reaches of the Empire was Agelaos. (PROSE: The Story of Martha: The Weeping)

At this time human colonists were fighting the centaur-like Aquabi on the planet Rescension. Pest Control (audio story)

The Earth was far less polluted in the empire's days than in the 20th Century. (TV: The Daleks' Master Plan)