george washington was the first president
Geothermal plateau. I'm only guessing, but since a lot of places use heat as energy it only makes sense.
They wouldn't really gain anything from killing, as a matter of fact it would be counter productive since people would gather against them because of it. They want total control over people and they want to break people physically and spiritually. Through torture they would eventually get the person to break and this would be good because they wouldn't be against the state anymore.
It decreased due to the fact that many jobs were opening in the urban areas so people left their farms and houses in rural areas to get a job in a bigger city.