Complex sentence: The close association between fashion and perfume is a modern phenomenon which took place most notably under the aegis of couturier Paul Poiret in 1911 when he turned to his friend Dr. Midy, the owner of a pharmaceutical laboratory, to explore perfume composition.
Split into simpler sentences: The close association between fashion and perfume is a modern phenomenon. The interconnection between the two took place most notably under the aegis of couturier Paul Poiret in 1911 when he turned to his friend Dr. Midy, the owner of a pharmaceutical laboratory, to explore perfume composition.