location

1. When we talk about possession, we can use " 's " or "of". But I don't know when to use 's and when to use "of" ?


2. Many peoples north and south of the grew rich from this trade. Are those people from Sahara but northern and southern areas Or those people are not from Sahara but north of and south of. I always feel confused about this kind of problem because I don' know 'north/ south of some place ' means it is still in this place or it is somewhere else. How about Southern Spain? Does it mean this place is still in Spain or it's not Spain anymore, but somewhere south.



THanks for help.