The first men on Mars are settlers strong enough to tame a wild frontier, and never mind those Indians—uh, we mean Martians—who were there before.
And the first women? "Everyone knew who the first women would be" (3). Translation: prostitutes, just like back in the good ol' days of the American West.
But mostly, this second wave of settlers consists of people from the cities looking for more space. Some of them are "on their way to God" (6).