Alberto Ginastera composed his 12 American Preludes near the end of his early, most explicitly nationalistic period. As exemplified in works such as the Danzas Argentinas, Op. 2, from 1937, and the Creole Faust Overture from 1944, Ginastera's first important pieces drew directly on regional folk styles and themes, especially those of his native Argentina. A similar approach can be found in the American Preludes, composed in 1944. The term "American" here is taken in a broader sense than Yankee listeners sometimes assume: the dozen short pieces in the series include musical evocations of, and tributes to, composers hailing from both North and South America. As Argentinean pianist Alberto Portugheis (arguably the foremost interpreter of Ginastera's piano music) described, "Ginastera tried in this work to translate musically the kaleidoscope of melodic and rhythmic turns similar to those of the American continent, from primitive pentatonic melodies to contemporary music." The works in the series are all miniatures ranging in length from 30 seconds to two minutes -- hardly constituting individual forms or developments at all, while instead conveying concise but vivid emotional evocations. Some of these are suggested only vaguely by the individual pieces' titles.
The opening piece, "Accents," consists of an unbroken chain of chords spanning the entire keyboard, their metric delivery made clear by an emphasis on triple divisions. The subsequent movement, bearing the simple title "Sadness," is an exercise in economy; a plain and plaintive melody in the right hand accompanied by sparse, single notes in the left, and a Spartan counterpoint that finds repose only in the subtle shift to the major mode near the piece's end. The rest of the series unfolds similarly, in a series of textural and temporal contrasts that includes a pair of studies in pentatonic modes that are anachronistic in their mixture of simple melodic materials and modern gestures. The lively "Creole Dance" is an angular, etude-like study; "Octaves" presages some of the more technically demanding moments in Ginastera's Piano Sonata No. 1 (1952); and the tranquil but mysterious "Pastorale" is constructed upon an unwavering two-note ostinato. Interspersed among the 12 pieces are tributes to specific American figures, including a furiously virtuosic ode to Roberto García Morillo; a melancholy melody dedicated to Juan José Castro; a playful, chromatically quirky tribute to Aaron Copland; and a dense, dark movement for Heitor Villa-Lobos.