Why is the phrase “with all deliberate speed” significant to the history of the civil rights movement?

 it meant a supposedly historic Supreme Court decision had little to no effect in terms of actual lived experience.
The phrase indicates that the government who at that time was expected to formulae the correct decision in handling racial-related problems was being really vague on where they stand on the matter.

He was an adventurer and writer who established a colony near roanoke island, in present day north coralina.