Grand Migration

The Great Migration was a mass exodus of sentient populace from Earth across space over the course of 2000 years, to their new home which would naturally come to be named New Earth. The Migration was orchestrated as a means to escape an event that ensured Earth's destruction and the extinction of all lifeforms therein, which is referred to historically as the Cataclysm. It was made possible by way of massive self-sustaining space station engineered by Scion Corporation, backed by the UN.

Migrants
By collective agreement from the UN, it was decided that the global economy be kept running to whatever degree the effectively doomed residents of Earth chose to participate; A new economic system would be put in place as a temporary system to not only help Scion Corporation incentivize its workers in order to develop the station, but act as a means for society to function normally during the extended period of time it would have to live solely aboard the station during the Migration. It was also decided that the top 5% of each nation currently active within the UN, based on a complicated list of factors, would be allowed to board the station in order to effectively preserve the exisistence of Earth's civilized world - However, not only would the very nature of these actions further strain the deteriorating fabric of civilization on Earth in the face of a coming apocalypse despite efforts to obscure the project, but entire races which either did not hold membership within the UN or were deemed not peaceable enough to coexist with those aboard the station were deliberately kept unaware of the project and left to their utter extinction.