19th-century adversary of an 80-Across Crossword Clue

 The 19th-century adversary of an 80-Across crossword clue is Beethoven. The 80-Across answer is Wagner.

Ludwig van Beethoven (1770-1827) and Richard Wagner (1813-1883) were two of the most important composers of the 19th century. They were both born in Germany and they both wrote operas. However, they had very different musical styles.

Beethoven was a classical composer who wrote in the traditional style. He was known for his complex and challenging music. Wagner, on the other hand, was a romantic composer who wrote in a more emotional and expressive style. He was known for his long and complex operas.

The two composers were also rivals. Beethoven was critical of Wagner's music, and Wagner was critical of Beethoven's music. However, they both had a profound impact on the development of music.

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