Otto Erich Deutsch, who studied all available letters and documents about the composer, arrived at the following conclusion about what the composer called himself: “In Italy, from 1770, Mozart called himself “Wolfgango Amadeo”, and from about 1777, “Wolfgang Amadè”.

The use of multiple language versions of the same name was perhaps common for composers in Mozart’s day. Joseph Haydn went by “Joseph” (English and French), “Josef” (German), and “Giuseppe” (Italian); and Ludwig van Beethoven likewise published as “Luigi” (Italian) and as “Louis” (French).

Mozart’s preference for “Wolfgang Amadè” can be seen on the wedding contract for his marriage to Konstanze Weber, dated August 3, 1782, where the composer’s signature is “Wolfgang Amade Mozart”. In the parish register entry for the marriage, dated August 4, Mozart is oddly referred to as “Herr Wolfgang Adam Mozart”, perhaps a bureaucratic error caused by the unfamiliarity of the name “Amadè”. Mozart biographer Maynard Solomon has developed a number of speculations on the meaning of “Adam”, under the assumption that its appearance is deliberate.

Mozart’s preference for “Amadè” was not in general respected by others. Frequently, he was called either “Wolfgang Amadeus” or “Wolfgang Gottlieb”, “Gottlieb” being yet another translation (German) of “Theophilus”. Here are examples, all dating from shortly after Mozart’s death.

• In a letter dated December 11, 1791, Mozart’s widow Konstanze, in severe financial straits, asked to be given a pension by the Emperor (the appeal was ultimately successful). She signed herself “Konstantia Mozart, née Weber, widow relict of the late Wolfgang Amadeus Mozart.” Imperial officials, replying to her request, used the same name.
• The parish register that recorded Mozart’s death gave his name as “Wolfgang Amadeus Mozart”.
• A benefit concert for Mozart’s family was held in Prague on December 28, 1791, billed as “Concert in memory of Wolfgang Gottlieb Mozart”.

Mozart’s final illness and death are difficult topics of scholarship, obscured by romantic legends and replete with conflicting theories. Scholars disagree about the course of decline in Mozart’s health—particularly at what point Mozart became aware of his impending death and whether this awareness influenced his final works. The romantic view holds that Mozart declined gradually and that his outlook and compositions paralleled this decline. In opposition to this, some contemporary scholarship points out correspondence from Mozart’s final year indicating that he was in good cheer, as well as evidence that Mozart’s death was sudden and a shock to his family and friends. The actual cause of Mozart’s death is also a matter of conjecture. His death record listed “hitziges Frieselfieber” (”severe miliary fever”), a description that does not suffice to identify the cause as it would be diagnosed in modern medicine. Dozens of theories have been proposed, including trichinosis, mercury poisoning, and rheumatic fever. The contemporary practice of bleeding medical patients is also cited as a contributing cause.

Mozart died around 1 a.m. on December 5, 1791 in Vienna, while he was working on his final composition, the Requiem. A younger composer, and Mozart’s only pupil at the time Franz Xaver Süssmayr, was engaged by Constanze to complete the Requiem. He was not the only composer asked to complete the Requiem but is associated with it over others due to his significant contribution.

According to popular legend, Mozart was penniless and forgotten when he died, and was buried in a pauper’s grave. In fact, though he was no longer as fashionable in Vienna as before, he continued to have a well-paid job at court and receive substantial commissions from more distant parts of Europe, Prague in particular. Many of his begging letters survive but they are evidence not so much of poverty as of his habit of spending more than he earned. He was not buried in a “mass grave” but in a regular communal grave according to the 1784 laws. Though the original grave in the St. Marx cemetery was lost, memorial gravestones (or cenotaphs) have been placed there and in the Zentralfriedhof. In 2005, new DNA testing was performed by Austria’s University of Innsbruck and the US Armed Forces DNA Identification Laboratory in Rockville, Maryland to determine if a skull in an Austrian Museum was actually his, using DNA samples from the marked graves of his grandmother and Mozart’s niece. However, test results were inconclusive, showing that none of the DNA samples were related to each other.

In 1809, Constanze married Danish diplomat Georg Nikolaus von Nissen (1761-1826). Being a fanatical admirer of Mozart, he edited vulgar passages out of many of the composer’s letters and wrote a Mozart biography.

Mozart had a special relationship with Prague and the people of Prague. The audience here celebrated their Figaro with the much deserved reverence he was missing in his hometown Vienna. His quote “Meine Prager verstehen mich” (My Praguers understand me) became very famous in the Bohemian lands. Many tourists follow his tracks in Prague and visit the Mozart Museum of the Villa Bertramka where they can enjoy a chamber concert. In Prague, Don Giovanni premiered on October 29, 1787 at the Theatre of the Estates. In the later years of his life, Prague provided Mozart many financial resources from commissions. German poet Eduard Mörike’s well-known novella Mozart auf der Reise nach Prag (”Mozart on the way to Prague”) is a fantasy about the composer’s trip to that city in order to present Don Giovanni (the story, however, relates episodes that happen along the way, not in Prague itself).

In 1781 Mozart visited Vienna in the company of his employer, the harsh Prince-Archbishop Colloredo, and soon fell out with him. According to Mozart’s own testimony, he was dismissed - literally - “with a kick in the seat of the pants.” Mozart chose to settle and develop his career in Vienna after its aristocracy began to take an interest in him.

On August 4, 1782, against his father’s wishes, he married Constanze Weber (1762-1842) (also spelled “Costanze”), a would-be cousin of Carl Maria von Weber. Although they had six children, only two survived infancy. Neither of these two, Karl Thomas (1784–1858) and Franz Xaver Wolfgang (1791-1844; later a minor composer himself), married or had children.

The year 1782 was an auspicious one for Mozart’s career; his opera Die Entführung aus dem Serail (”The Abduction from the Seraglio”) was a great success and he began a series of concerts at which he premiered his own piano concertos as conductor and soloist.

During 1782–83, Mozart became closely acquainted with the work of J.S. Bach and George Frideric Handel as a result of the influence of Baron Gottfried van Swieten, who owned many manuscripts of works by the Baroque masters. Mozart’s study of these works led first to a number of works imitating Baroque style and later had a powerful influence on his own personal musical language, for example the fugal passages in Die Zauberflöte (”The Magic Flute”) and the Symphony No. 41.

In 1783, Wolfgang and Constanze visited Leopold in Salzburg, but the visit was not a success, as his father did not take to Constanze. However, the visit saw the composition of one of Mozart’s great liturgical pieces, the Mass in C Minor, which was premiered in Salzburg, and is presently one of his best known works.

In his early Vienna years, Mozart met Joseph Haydn and the two composers became friends. When Haydn visited Vienna, they sometimes played in an impromptu string quartet. Mozart’s six quartets dedicated to Haydn date from 1782–85, and are often judged to be his response to Haydn’s Opus 33 set from 1781. Haydn was soon in awe of Mozart, and when he first heard the last three of Mozart’s series he told Leopold, “Before God and as an honest man I tell you that your son is the greatest composer known to me either in person or by name. He has taste, and what is more, the most profound knowledge of composition.”

During the years 1782-1785, Mozart put on a series of concerts in which he appeared as soloist in his piano concertos, widely considered among his greatest works. These concerts were financially successful. After 1785 Mozart performed far less and wrote only a few concertos. Maynard Solomon conjectures that he may have suffered from hand injuries; another possibility is that the fickle public ceased to attend the concerts in the same numbers.

Mozart was influenced by the ideas of the eighteenth century European Enlightenment as an adult, and became a Freemason (1784). His lodge was a specifically Catholic rather than a deistic one and he worked fervently and successfully to convert his father before the latter’s death in 1787. His last opera, Die Zauberflöte, includes Masonic themes and allegory. He was in the same Masonic Lodge as Haydn.

Mozart’s life was fraught with financial difficulty and illness. Often, he received no payment for his work, and what sums he did receive were quickly consumed by his extravagant lifestyle.

Mozart spent 1786 in Vienna in an apartment (in the “Mozarthaus”) which may be visited today at Domgasse 5 behind St Stephen’s Cathedral; it was here that Mozart composed Le nozze di Figaro. He followed this in 1787 with one of his greatest works, Don Giovanni.

Leopold realized that he could earn a substantial income by showcasing his son as a Wunderkind in the courts of Europe. Mozart soon gained fame as a musical prodigy capable of such feats as playing blindfolded or competently improvising at length on difficult passages. His older sister Maria Anna (Nannerl) was a talented pianist and accompanied her brother on the earlier tours. Mozart wrote a number of piano pieces, in particular duets and duos, to play with her. On one occasion when Mozart became very ill, Leopold expressed more concern over the loss of income than over his son’s well-being.

During his formative years, Mozart completed several journeys throughout Europe, beginning with an exhibition in 1762 at the Court of the Elector of Bavaria in Munich, then in the same year at the Imperial Court in Vienna. A long concert tour spanning three and a half years followed, taking him with his father to the courts of Munich, Mannheim, Paris, London, The Hague, again to Paris, and back home via Zürich, Donaueschingen, and Munich. They went to Vienna again in late 1767 and remained there until December 1768.

After one year in Salzburg, three trips to Italy followed: from December 1769 to March 1771, from August to December 1771, and from October 1772 to March 1773. During the first of these trips, Mozart met Andrea Luchesi in Venice and G.B. Martini in Bologna and was accepted as a member of the famous Accademia Filarmonica. A highlight of the Italian journey, now an almost legendary tale, occurred when he heard Gregorio Allegri’s Miserere once in performance in the Sistine Chapel then wrote it out in its entirety from memory, only returning to correct minor errors; he thus produced the first illegal copy of this closely-guarded property of the Vatican [source documents].

On July 3, 1778, accompanied by his mother, Mozart began a tour of Europe that included Munich, Mannheim, and Paris, where his mother died.

During his trips, Mozart met a great number of musicians and acquainted himself with the works of other great composers. A particularly important influence was Johann Christian Bach, who befriended Mozart in London in 1764–65. Bach’s work is often taken to be an inspiration for the distinctive surface texture of Mozart’s music, though not its architecture or drama.

Even non-musicians caught Mozart’s attention. He was so taken by the sound created by Benjamin Franklin’s glass harmonica that he composed several pieces of music for it.

Mozart was born on January 27th, 1756, in the city of Salzburg, the capital of the independent archbishopric of Salzburg, which today is part of Austria, to Leopold and Anna Maria Pertl Mozart. He was baptized the day after his birth at St. Rupert’s Cathedral. The baptismal record gives his name in Latinized form as Johannes Chrysostomus Wolfgangus Theophilus (Gottlieb) Mozart. Of these names, the first two were saint’s names not employed in everyday life and the fourth was variously translated in Mozart’s lifetime as Amadeus (Latin), Gottlieb (German), and Amadé; Mozart himself preferred the third (see Mozart’s name).

Mozart’s musical ability became apparent when he was about three years old. His father Leopold was one of Europe’s leading musical pedagogues, whose influential textbook Versuch einer gründlichen Violinschule (”Essay on the fundamentals of violin playing”) was published in 1756, the year of Mozart’s birth. Mozart received intensive musical training from his father, including instruction in clavier, violin, and organ.