The Martian Chronicles is a history of the settlement of Mars by Earthians. The first three expeditions fail, and all of
their crews are killed by the native Martians; by the fourth expedition, most all the Martians have succumbed to Earthian chickenpox and were killed. Despite the actions of a crewmember of this expedition who was sympathetic to Martian culture, a foothold on the planet was established and colonization began.
This colonization was exclusively by the United States of America, as other nations were tied up in international struggles. There were some Martians left on Mars, who interacted sporadically with Earthian
settlers. On the eve before a hundred thousand Chinese and Mexican settlers were to arrive, the Great War began on Earth. Instead of a sizeable increase in Earthian
colonizers to Mars, there was a return by colonizers back to Earth until the planet was left almost entirely uninhabited.
Twenty years after the Great War and at the brink of human civilization's final collapse, some Earthians escaped their home planet to start over in Mars.