ORIGIN OF POPULAR SAYINGS
Meaning: The darkest hour is the time when bad events are at their worst and most dispiriting.
Background: The expression 'the darkest hour' came into widespread use in early 19th century England. However, the usage of the phrase that has more recently become popular originated well before that, in the proverb 'the darkest hour is just before the dawn'. A version of the proverb was recorded by Thomas Fuller in A Pisgah-Sight Of Palestine And The Confines Thereof, 1650: It is always darkest just before the Day dawneth.
Meaning: A 'chip on your shoulder' is a perceived grievance or sense of inferiority.
Background: The phrase 'a chip on one's shoulder' is reported as originating with the nineteenth century U.S. practice of preparing for a fight by carrying a chip of wood on one's shoulder, daring others to knock it off. This suggested derivation has more than the whiff of folk-etymology about it. Anyone who might be inclined to doubt that origin might be interested in an alternative theory. This relates to working practices in the British Royal Dockyards in the 18th century.