Zelenka was born in Louňovice pod Blaníkem, a small market town southeast of Prague in what was then Bohemia. His father was a schoolmaster and organist there; nothing more is known with certainty about Zelenka's early years. He probably received musical training in the center of Prague at a Jesuit college named the Clementinum. Zelenka played the violone, the largest and lowest member of the viol family, analogous to the double bass in the violin family of stringed instruments.
It is known that Zelenka served Baron Hartig, the imperial governor resident in Prague, before becoming a violone player in the royal orchestra at Dresden about 1710. He studied in Vienna with the Hapsburg imperial Kapellmeister Johann Jacob Fux from 1715 - according to his own account he spent 18 months in Vienna - and was back in Dresden by 1719. Except for a visit in 1723 to Prague to take part in the performance of Fux's opera Constanza e Fortezza, he remained a resident of Dresden until his death. Whether or not he ever went to Venice is unclear, but a Saxon court document of 1715 records a royal cash advance for such a journey by Zelenka along with Christian Petzold, Johann Georg Pisendel, and J. C. Richter.
In Dresden, Zelenka initially assisted the Kapellmeister, Johann David Heinichen, and gradually assumed Heinichen's duties as the latter's health declined. After Heinichen died in 1729, Zelenka applied for the post of Kapellmeister, but the post was given instead (in 1733) to Johann Adolf Hasse, reflecting the court's interest in opera as opposed to liturgical music. Instead, in 1735, Zelenka was given the title of "church composer" ("Compositeur of the Royal Court Capelle"). (J.S. Bach had applied for this title in 1733, and was to receive it as well in 1736.)
Zelenka died of edema in Dresden in 1745, having written works in his final years that were never performed during his lifetime. He never married and had no children; his compositions and musical estate were purchased from his beneficiaries by the Electress of Saxony, Maria Josepha of Austria.
There is no known portrait of Zelenka. (A mirror-image black-and-white takeoff of the well-known portrait of Fux has been passed off as a picture of Zelenka on several respected websites.)
Most of Zelenka's compositions were sacred works, including three oratorios, 21 masses, a Te Deum and numerous other pieces of music. Zelenka's orchestral and vocal pieces are often virtuosic and difficult to perform. In particular, his writing for bass instruments is far more demanding than that of other composers of his era, notably the "utopian" (as Heinz Holliger describes them) demands of the oboe scores in his trio sonatas.
J. S. Bach held Zelenka in high esteem, as evidenced by a letter from Bach's son C. P. E. Bach to J. N. Forkel, of 13 January 1775, and Zelenka was a guest at Bach's home in Leipzig.
It was mistakenly assumed that many of Zelenka's autograph scores were destroyed during the fire-bombing of Dresden in February 1945. However, the scores were not in the Catholic cathedral, but were in a library north of the river. Some are certainly missing, but this probably happened gradually - and these represent only a small proportion of his extant works.
The music of Zelenka has become widely known and available since the 1970s because of recording and the interest of musicians such as Heinz Holliger and Reinhard Goebel.
More than half of Zelenka's works have now been recorded, mostly in the Czech Republic and Germany. The Missa Purificationis (ZWV 16) is the latest to appear (on Nibiru Records; see below). Some would say that this mass reflects Zelenka at his peak, as at the time (1733) he was very much in the limelight at the Dresden court. (This is the last mass to include brass instruments). Others would say that Zelenka's compositional peak corresponds to his final masses from 1739-1744 (ZWV 19-21).
Zelenka was clearly aware of the music that was being composed and performed in different regions of Europe. His style consists of complex, contrapuntal fugues, ornately operatic arias in masses and oratorios, the galant style that was beginning to take popular grounds in the 18th century, baroque recitative-like writing, Palestrina-like chorale writing, and virtuosic writing for instruments in concertos and sonatas. Compared to the musical language of Bach's contemporaries, Zelenka's musical language is closest to that of Bach's especially in its richness of contrapuntal harmonies and ingenious usage of fugal themes, yet Zelenka's language is idiosyncratic in its unexpected harmonic twists, obsession with chromatic harmonies, huge usage of syncopation and triplet figures, and unusually long phrases full of varied musical ideas.
His instrumental works (the trio sonatas, capricci, and concertos) are exemplary models of his early style (1710s - 1720s). The six trio sonatas demand high virtuosity and great expressive sensitivity on oboists, bassonists, violinists, and even continuo players. Because Zelenka was himself a violone player, Zelenka was very fond of bass instruments and wrote fast-moving continuo parts with driving and complicated rhythm.
Lamentationes Jeremiae Prophetae (Lamentations of the Prophet Jeremiah)
Die Responsorien zum Karfreitag (Responses for Good Friday)
More than 20 masses (designated ZWV 1–21)—some missing—and a number of mass movements. Missa Purificationis,Missa Sanctissimae Trinitatis,Missa Votiva,Missa Dei Patris,Missa Dei Filii, and Missa Omnium Sanctorum (designated ZWV 16–21) rank amongst Zelenka's finest works.
Ten litanies, including 2 Litaniae Lauretanae (ZWV 151 & 152)
Four requiem settings (of which one—ZWV 45—has only been attributed to Zelenka)
Fifty-three psalm settings, some missing
Sub olea pacis et palma virtutis—Melodrama de St. Wenceslao (ZWV 175)
Gesù al Calvario, oratorio (ZWV 62)
I Penitenti al Sepolcro del Redentore, oratorio (ZWV 63)