Final answer:
The Baroque era was the first era in Western music history where instrumental music was as important as vocal music.
Step-by-step explanation:
The first era of Western music history in which instrumental music was as important as vocal music was the Baroque era. During this time, instrumental music gained significance and composers like Johann Sebastian Bach and Antonio Vivaldi were known for their instrumental compositions. The Renaissance and Middle Ages primarily focused on vocal music, while the 19th century saw a shift towards concert music.
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