Late Romanticism's excess set the stage for a stylistic rebellion

Ross opens with composers like Richard Strauss and Gustav Mahler pushing late Romantic orchestral music toward its emotional and harmonic extremes, enormous orchestras, lush chromatic harmony stretched to its outer edges, music of overwhelming size and feeling that seemed to be reaching some natural ceiling of what tonal, Romantic expression could still do.

He frames this excess as creating the conditions for the century's coming rebellion: once Romantic harmony had been pushed about as far as it could go without abandoning tonality altogether, the next generation of composers faced a genuine crossroads, either keep intensifying an already maximal style, or break from tonal harmony's basic assumptions entirely.

Ross treats this moment as a hinge point for the whole century, since the decision different composers made here, whether to preserve tonal language in some form or abandon it, produced two of the era's most consequential and durable divides.

Takeaway: revolutionary breaks in art often follow a period where the existing style has been pushed to genuine exhaustion.