Johann Heinrich Schmelzer (or Schmelzer von Ehrenruef) might have created considerable confusion himself over his true biography. On his sister's marriage certificate, the head of their family is identified as Daniel Schmelzer, a baker and burgher of the town of Scheibbs. But Johann Henrich applied in 1673 for documents of ennoblement and claimed his father was an officer in the army of Emperor Ferdinand II. The earliest documentation of his life is the certificate for his first marriage on June 28, 1643, which describes him as a cornettist at St. Stephen's Cathedral in Vienna. He may have been a court chapel violinist as early as 1635, and on October 1, 1649, he was appointed as a violinist in the court orchestra. There are few details of his life and career, but he wrote considerable quantities of music. Between 1659 and 1664, he published three important collections of chamber music. In 1660, composer J. Müller called him "the famous and nearly most distinguished violinist in Europe."
He enjoyed the favor of Emperor Leopold II and had been appointed to head the musicians in the retinue accompanying Leopold in 1658 to his coronation in Frankfurt am Main. The Emperor was a composer himself who frequently sought Schmelzer's professional opinion and relied on him to prepare performances of his music. As a result, he gave Schmelzer frequent gifts of money and golden chains (the latter indicated special favor).
While he wrote his share of vocal and sacred music, Schmelzer's fame and influence are primarily due to his instrumental music. He wrote nearly all of the dramatic music played at court from 1655 to 1680, including ballet music, allegorical pageants, and incidental music to spoken dramas. The court was given to lavish spectacles in which members of the royal family often took part. From this music, Schmelzer arranged dance suites, which were important to the development of the German orchestral suite. These often began with an intrada, ended with a retirada, and included a variety of dance forms (as many as nine individual numbers). He unified these suites by using shared motives, but achieved variety by being quite free in the succession of tonalities. The scoring of these suites was generally for consorts of stringed instruments, but he sometimes added cornets, clarini, trumpets, bassoons, trombones, and piffari.
Schmelzer's chamber music often includes two melody instruments and continuo. One of his most important sets of compositions was his six violin sonatas called Sonatae unarum fidium from 1664. Variations were typical in his sonatas and these were virtuosic. Again, his music in this genre was influential in future development of German instrumental music.
When the post of vice-imperial court Kapellmeister fell vacant on April 13, 1671, the Emperor appointed him to that position. The incumbent in that position, G.F. Sances, was an aged, ailing man, and so Schmelzer did the organizational work and most of Sances' other duties. Handling these responsibilities well, his rising fame, and Leopold's admiration, no doubt led the Emperor to grant that 1673 petition for ennoblement. At that point, Schmelzer added the noble "von Ehrenruef" to his name, and it was inherited by his sons. Sances died on November 24, 1679, and Schmelzer petitioned the Emperor on December 18 for the vacant position. The delay might be accounted for by the need to move the court to Prague while Vienna was struck by the plague. The Emperor granted it, retroactive to October 1 (Schmelzer had asked for July 1), but within three months, Schmelzer had died, probably of the plague.