The Native Americans used the buffalo for food and clothing. The Native Americans did believe in wasting any part of the animal.They used they buffalo's entire body including the bones for tools.
I interpret "Him" here to mean God (this is why it's written in a capital letter).
So, Hitler thanks God that it was possible for him to return to Austria- a country where he was born but where he hasn't lived in a long time- and by returning to Austria he joins Austria with Germany, which he believes it should always have been ('return").
His biggest problem was that he was wrong about the circumference of the earth. He was lucky there was a continent unknown to Europe where he though Asia was, or he would have sailed into obscurity.
Filth (like sewages)= how to keep it from potable water sources. Crime = too many poor people and not enough income available.
Disease = they were pretty dirty people, disease & death were at high rates.. many infected bodies to dispose of.