Fiesque Composer

Answer is: French composer Eduardo Lalo.

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Goddes of Folly

The Name of the Goddes of Folly is Moria (in Greek) or Stultitia (in Latin)

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Arboreal Lemur

In short, the answer that you seek is Indri. A large arboreal lemur of Madagascar, having large eyes and a rudimentary tail.

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Die Lorelei Poet

Answer is: Heinrich Heine.

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Composer Mahler

Gustav Mahler. Bohemian-Austrian composer and conductor.

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Actress Menken

Adah Isaacs Menken, the first American Jewish “superstar.”