Dorothy Arzner wasn’t the first female film director in the U.S., but she was really the only one working in the studio system during most of the period that’s known as the Hollywood Golden Age. Her short career was still incredibly prolific.
Research:

Great Lisbon Earthquake of 1755
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Benzedrine, Pervitin, and WWII
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SYMHC Classics: COINTELPRO 1
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