In the 21st and 22nd centuries (SEY 2038 - 2157), population levels on Earth (Sol III) began to rise beyond sustainable capacity. Pollution, dwindling resources, and famine affected all nations of the world, leading to overcrowding in the few unspoiled places left on the planet. Natural wonders previously under protection from their governments were bulldozed over in favor of creating settlements or potential arable land. Countless animal and plant species became extinct. The successful terraforming of Mars (Sol IV) in 2157 provided a much-needed outlet for the populace, ending the Overpopulation Era and opening the path to the stars.