Italian composer, son of the musician Carlo Porsile, whose opera Nerone was produced, according to Burney, at Naples in 1686. He studied with Ursino, Giordano, and Greco at the Conservatorio dei Poveri di Gesu Cristo in Naples, and was named vice-maestro di cappella at the Spanish chapel in Naples. He was called to Spain in 1695 by Charles II to organize the music chapel at Barcelona, and remained there under Charles III, the Austrian contender to the Spanish throne, and served as singing-master to Charles’s wife Elisabetta Cristina. To what extent he was also active as a teacher and composer in Naples before 1713 remains unclear, but his early opera Il ritorno di Ulisse was produced there in 1707.Charles was named CharlesVI, Holy Roman Emperor, in 1711, and Porsile followed him to Vienna in 1713, becoming court composer in 1720.
According to Otto Biba, Porsile arrived in Vienna in the same year and began to give singing lessons to the dowager Empress Wilhelmina Amalia, for whose birthday and nameday he wrote at least three dramatic works. The elaborate birthday cantata of 1717 was sung for the imperial family by the dowager empress's daughters, the Archduchesses Maria Josepha and Maria Amalia. His initial annual salary of 200 ducats was not confirmed until 1717, and while being promised a more substantial appointment he served as /attuario di camera/. In a letter to the emperor dated 27 November 1720 (printed in La Mara), he complained of financial hardship, reminded the emperor of his long service and asked for a permanent position. On 17 December 1720 he succeeded Gregorio Genuesi as court composer with a salary of 1440 florins.
Between 1717 and 1737 Porsile produced at least 21 secular dramatic works and 13 oratorios for the Habsburg court. Only a few works received performances outside Austria, in cities such as Venice and Prague. /Il giorno felice/ was composed for the coronation of Charles VI and Elisabetta as King and Queen of Bohemia and performed at Prague in 1723. In 1726 Porsile composed an elaborate cantata, /Il giorno natalizio di Giove/, which was performed at the palace of the French ambassador in honour of the birthday of Louis XV of France. In the same year another imperial court composer, Francesco Conti, wrote a similar cantata for the nameday of Louis XV, also performed at the French Ambassador's palace. The Emperor's unusual decision to permit his court composers to provide music for occasions honouring French royalty may have been part of a general plan to improve diplomatic relations with France, or simply a polite gesture during a year of celebration following the marriage of Louis XV to the Polish Princess Maria Leszczynska on 5 September 1725.
During 1725–7 Porsile was active as a member of the Viennese Caecilien-Bruderschaft, whose deans were Fux and Caldara. In 1729 he became marginally involved in a lawsuit by Matteo Luchini against the soprano Margherita Gualandi, who had left Prague at the end of the operatic season without paying Luchini for 12 'baggage arias'. Porsile was one of four prominent composers who wrote to the legal authorities in Prague on behalf of Luchini; in his letter of 29 June (transcr. Freeman, /The Opera Theater/, p.292) he indicated that it was not difficult to produce 12 arias, but that they were certainly worth the 12 ducats Luchini requested. After the death of Charles VI in 1740 he continued to receive an honorary stipend, which was lowered to 1200 florins in 1741. He was awarded a final pension on 1 April 1749.
The bulk of Porsile's output consists of over twenty secular dramatic works and thirteen oratorios, most premiered in Vienna. Although Porsile’s music is overshadowed by that of his Viennese contemporaries, Fux and Caldara, its fusion of Neapolitan and north Italian elements was an important ingredient in the development of pre-Classical style in Vienna.