Ginastera was born in Buenos Aires in 1916, and even in his childhood showed early promise as a performer and composer. His adolescent years were spent in formal studies at the Williams Conservatory, and within a few years of his admittance to the National Conservatory as an undergraduate, his music was receiving national acclaim in prominent performance venues. His initial reputation rested largely on his creative interpretations of and allusions to Argentinean folk materials, as realized in short-form pieces and suites, but by the late '40s and early '50s he had completed a number of more imposing works, such his Piano Sonata No. 1 and his first two string quartets. He had also ventured abroad, first to Tanglewood in 1941, where he became fast friends with Copland, then to other destinations throughout the U.S. in the late '40s, and finally to several venues in Europe during the early '50s, where works such as the Variaciones concertantes and Pampeana No. 3 enjoyed warm receptions. He likewise introduced internationally acclaimed composers to Argentina; he oversaw an ambitious department at Catholic University (1958-1963), and during his tenure as director of the Latin American Centre for Advanced Musical Studies (1963-1971) his invited guests included Messiaen, Nono, Dallapiccola, and Xenakis. Ginastera's works from the '60s, including the opera Don Rodrigo (1963-1964), grew more varied in their methods and ambitious in their scope.
Ginastera worked actively as a composer and champion of new music despite considerable external obstacles; his political views twice put him at odds with the Perón government, which forced his resignation from positions at the National Military Academy and the National University of La Plata (he regained the latter position after Perón's defeat). Personal problems, including marital strife, stifled his productivity in the late '60s, but his divorce and subsequent marriage to cellist Aurora Natola, and his retirement to Switzerland after decades of teaching in Argentina's most prominent musical institutions, gave Ginastera his second wind; his last years were among his most fruitful.