Second Great and Bountiful Human Empire

The Second Great and Bountiful Human Empire was a Human-ruled empire, with colonies in Mutter's Spiral and another two galaxies. By this time, Earth was a crowded planet. The currency of the Empire was the credit. (DW: Planet of the Ood)
 * Most likely this was also the empire referred to in The Impossible Planet, which send out the Walker Expedition

History
The Empire began sometime in the fourth millennium, almost certainly after the fall of the First Earth Empire and before the enslavement of the Ood in the 3800s. The Empire itself was built on the Ood slave trade, but apparently survived after the trade collapsed with Ood freedom in 4126. (DW: Planet of the Ood)