The New Earth Empire was the governing body of humans, established prior to the destruction of Earth in the year 5,000,000,000.
Circa 4,999,999,740, the planet New Savannah was inducted into the New Earth Empire. (COMIC: Agent Provocateur)
By 5,000,000,023 AD, humanity was fully established (with a population of at least ten million) on the planet New Earth, after the original had been destroyed 23 years earlier. The planet had a similar orbit, atmosphere, and size to the original Earth. (TV: New Earth)