Mozart composed the aria in October 1765 while staying at The Hague during the family's British-European tour, when he was nine years old. Both of the Mozart children, Wolfgang and his sister Nannerl, were quite ill at the time. It was slightly revised in January 1766, possibly for a performance for Princess Carolina of Orange-Nassau. In his list of Wolfgang's works which he started in 1768 in Vienna, his father Leopold entered this piece as no. 2 of 15 Italian Arias, composed in London and The Hague (German: 15 Italiänische Arien theils in London, theils im Haag Componiert).
The Newberry Library (Case MS 6A, 48), Chicago, acquired the manuscript (6 sheets, 11 pages) through a bequest of the opera singer Claire Dux –Mrs Charles H. Swift– (1885–1967 in Chicago). It was previously owned by Raphael Georg Kiesewetter who gave the autograph to Aloys Fuchs as a gift. Both Fuchs and Abbé Maximilian Stadler confirmed its authenticity with their signatures on 7 December 1832. The Neue Mozart-Ausgabe also mentions an autograph (4 sheets, 7 pages) at the Bibliothèque nationale de France in its Malherbe collection.
The text is taken from Metastasio's libretto Artaserse which had been set to music by a number of composers, among them Johann Christian Bach whom Mozart had met just a short time before in London. Other Mozart works based on Metastasio texts include his last opera, La clemenza di Tito, and the earlier Il re pastore.
The lyrics chosen by Mozart are the parting verses of Artaserse's sister, Mandane, in act 1, scene 1, as she bids farewell to her lover Arbace:
Pensa ch'io resto, e peno,
E qualche volta almeno
Ricordati di me.
Ch'io per virtù d'amore,
Parlando col mio core,
Ragionerò con te.
Stay and remain faithful;
Think how I grieve alone here,
And sometimes at the least
While I by power of love
Talking to my own heart
Converse with thee.
The text of "Conservati fedele" has also been set to music by Leonardo Vinci (1690–1730) and Hasse (1699–1783) in their respective operas Artaserse, by Antonio Salieri and Marianne von Martines (1744–1812) as concert arias, twice by Joseph Martin Kraus (1756–1792), by Ferdinando Carulli (1770–1841) for voice and guitar, and by Theodor von Schacht (1748–1823) as a canon for three equal voices accompanied by cembalo and/or guitar.
The work is scored for soprano, two violins, viola, cello and bass; the tempo marking is Andante grazioso, the time signature is 2/4 time, the key signature is A major. A typical performance would last for about 7 minutes.
It is composed as a da capo aria (bars 1–86) with a short middle section ("Ch'io per virtù d'amore", bars 87–100) which has the tempo marking Allegretto and is in the parallel key of A minor. The aria consists almost wholly of two-bar phrases.
After hearing this piece and "Va, dal furor portata" (K. 21) written by the nine year-old Mozart, Baron Grimm predicted that "the boy would have an opera performed in an Italian theatre before he was twelve". As it turned out, Mozart's first work for the stage, Die Schuldigkeit des ersten Gebots, was performed less than 18 month later, and his first work for an Italian theatre, Mitridate, re di Ponto, opened in Milan in 1770 when Mozart was 14 years old.
- Neue Mozart-Ausgabe, II/7/1: "Arien, Szenen, Ensembles und Chöre mit Orchester, vol. 1, pp. IX–XI (German)
- Research Materials of the BMEO from the Loeb Music Library, Harvard University
- Irving Godt: "Marianna in Italy: The International Reputation of Marianna Martines", in: The Journal of Musicology, Vol. 13, No. 4 (Autumn, 1995), p. 558, University of California Press
- Notes from Mozart: The Concert Arias / Te Kanawa, Gruberova, et al.
- Opera Glass: Mozart arias
- Cliff Eisen, Simon P. Keefe: The Cambridge Mozart Encyclopedia, Cambridge University Press, 2006. p. 286, ISBN 978-0-521-85659-1
- Stanley Sadie, Neal Zaslaw: Mozart: The Early Years 1756–1781, Oxford University Press, 2006. p. 107–108, ISBN 978-0-19-816529-3
- Conservati fedele: Score and critical report (German) in the Neue Mozart-Ausgabe