About one year later, the American composer Frederic Rzewski heard the song in a concert at Hunter College in New York and used it as the kernel for an epic set of piano variations. Think of it as the Goldbergs of revolution. "The People United Will Never Be Defeated!" has become a landmark of the modern piano repertoire.
It also apparently has a way of turning up where you least expect it, like at a concert at Wellesley College on Wednesday. The pianist was the inimitable Stephen Drury, an excellent interpreter of new music and a seemingly under-showcased faculty member at New England Conservatory.
Stretching nearly an hour in length, "The People United" begins and ends with a poignant statement of Ortega's theme, and in between these two bookends come 36 variations in which all hell breaks loose. The variations range from muscular and rhythmically explosive to liquid and dreamlike. Some come across as virtuosic Lisztian experiments that push the bounds of sonic anarchy; others pulverize the melody beyond recognition and then float it quietly above the wreckage. At a few points, Rzewski takes leave of conventional piano technique altogether and asks his soloist to shout, to whistle, and to slam the piano lid. Most remarkable of all is the sense of organic unity that the composer forges in the face of such kaleidoscopic variety.
For his part, Drury was superb. He has recorded this piece on the New Albion label, and his performance on Wednesday, played from memory, was the kind of sweeping act that erases distinctions between brilliant technique and deep musical understanding. In the final few minutes, when Ortega's song at last returns in its simple and unadorned grandeur, Drury played with a broad, majestic tone that perfectly captured the feeling of arrival, all the more powerful for being so hard-won.
Standing up to take his bows, the pianist looked out into the modest hall. The undergraduates behind me shuffled to their feet, clutching spiral notebooks and looking slightly dazed. It had been quite a lunchtime lecture. The ovation was small but heartfelt.
Jeremy Eichler can be reached at jeichler@globe.com.