How did european countries decide where to draw the new boundaries in africa?

When different European countries in the 17-19 centuries captured the colony-then at some point there was a need to delineate the overseas possessions. Otherwise, we would have to fight much more often and more. And for differentiation, in general, there was only two ways-on natural-geographical basis: on a big river, a mountain ridge. There are such borders in Africa. And if there is no natural geographical characteristic? Then we had to draw on the map.

"the sepoy rebellion was the result of many, many influences and stressors on the cultures of india living under british rule. in britain, it's called the sepoy mutiny on the indian mutiny, but in india, it's called the first war of independence.

the main reason is concerned to the british paramountcy , the belief in british   dominance in india political, economic and cultural life had been introduced in india about 1820."

"they were forced to grow crops that benefited the colonizing nations instead of feeding their own people."

besides the fact that abraham lincoln abolished slavery, and greatly benefit black people, he had a heavy impact of the definition of what democracy was, and should be.