Why were the middle ages also referred to as the dark ages?

Answer 1

the middle ages/medieval taimes/dark ages were not named as such until after the fact. the thinkers of the renaissance (which was very localized) refered to it as that because they were entering a new age of light, as in knowledge. therefore, the time before this must have been "dark" by default. also, it is called the middle ages by the same renaissance thinkers because it was the time period in between the greatness of the antiquities of rome and greece and their current(in the 14th and 15th cent.) quest for knowledge and a reversion to the antiquities and classics. also, in the same vein, the reaissance was not named until after the fact as well.

Answer 2

See http://en.wikipedia.org/wiki/Dark_ages for an explanation.

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