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In page Christoph Willibald Gluck:

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In Vienna, Gluck met like-minded figures in the operatic world: Count Giacomo Durazzo, the head of the court theatre, and one of the primary instigators of operatic reform in Vienna ; the librettist Ranieri de' Calzabigi, who wanted to attack the dominance of Metastasian opera seria; the innovative choreographer Gasparo Angiolini; and the London-trained castrato Gaetano Guadagni.[citation needed]