Nature and environment had a big play in the development in early civilizations because that was there foundation to there survival and being able to expand there civilizations, also many of the early civilizations had very strong beliefs based on nature and agriculture that shaped their civilizations and cultures
Its kinda confusing maybe try putting a pic to understand better
The louisiana purchase in 1803 doubled the size of america
The desert which covers much of Botswana is called the Kalahari Desert.
Not sure what you're looking for exactly, but they were certainly risking their lives and livelihoods. African-Americans weren't the only people to be lynched in the fight against racism- black and white abolitionists were at risk as well (though certainly whites to a lesser degree).