On January 5, he entered a new piano concerto (No. 27 in B-flat, K. 595) into his catalogue—a work he had begun back in 1788. In January he also finished three songs for voice and piano and a dozen dances for orchestra, followed by twenty more the following month.

On March 4, he performed the B-flat major concerto at Jahn's Hall in Vienna. Four days later, he finished the concert aria Per questa bella mano (“By this fair hand,” K. 612), on a text taken from a now-forgotten Italian opera.

In this work, the bass singer is joined by a solo double bass—the only instance Mozart ever used that instrument in a solo role. A brilliant virtuoso showpiece for both bassists, it was the first fruit of his professional association with Emanuel Schikaneder, his artistic partner in The Magic Flute: both the singer Franz Gerl (the future first Sarastro) and the double-bass player Friedrich Pichelberger worked in Schikaneder's theater.

Still in the same month, Mozart's extraordinary Adagio and Allegro for a mechanical organ (K. 594), written the previous year, was played at a waxwork gallery during a memorial for a deceased military leader.

I have now made up my mind to composer at once the Adagio for the clockmaker and then to slip a few ducats into the hand of my dear little wife. And this I have done; but as it is a composition which I detest, I have unfortunately not been able to finish it. I compose a bit of it every day—but I have to break off now and then, as I get bored. And indeed I would give the whole thing up, if I had not such an important reason to go on with it. But I still hope that I shall be able to force myself gradually to finish it. If it were for a large instrument and the work would sound like an organ piece, then I might get some fun out of it. But, as it is, the works consist solely of little pipes, which sound too high-pitched and too childish for my taste.
—Mozart to his wife, October 3, 1790

In the spring, Mozart composed one more work for mechanical organ (the Fantasy in F minor, K. 608), as well as two pieces for glass harmonica. A set of variations for piano (“Ein Weib ist das herrlichste Ding,” K. 613) was written in March, and the last of the great string quintets, a work in E-flat major (K. 614), was finished in Apirl.

Those who believe the story told in so many Mozart biographies, namely that the composer never heard his last three symphonies, should be reminded of a documented performance of the G-minor work (No. 40, K. 550, written in 1788) at the Court Theatre on April 16. Soon afterwards, Mozart was appointed Assistant Kapellmeister at St. Stephen's Cathedral, although he doesn't seem to ever have actually conducted there. That should come as no surprise, however, if one bears in mind that he was already working on The Magic Flute and by the summer, had received the contract for La clemenza di Tito as well. Both operas were to be premiered in September, The Magic Flute in Vienna and Tito at the coronation of Emperor Leopold II in Prague, no less!

In short, Mozart was busier in 1791 than he had ever been before. And if that were not enough, Constanze was pregnant for the sixth time (she had lost four of her children in infancy). In June, she left Vienna to take the waters in nearby Baden, taking six-year-old Karl, her only surviving child, with her. Throughout June and July, Mozart shuttled back and forth between Vienna and Baden, where he had to cultivate a good relationship with the local choirmaster, Anton Stoll, who helped look after Constanze. He wrote the short motet Ave verum corpus (K. 618), dated June 17, for Stoll as a token of his gratitude.

Only a genius can write something as simple yet as profoundly moving as Ave verum corpus Four lines of music, a gentle, yet highly effective change of keys strategically placed in the third line, and a slight extension of the last line just before the close—that’s all, and yet, how much more there is that words can’t begin to express! The surprising harmonic turn on the first ‟in mortis examine” returns in the ‟March of the Priests” from The Magic Flute, which is hardly a coincidence: in both works, written around the same time, the harmony in question enhances the spiritual atmosphere, keeping the music off the ground just a moment longer before the final arrival on the tonic chord.

When you are bathing, do take care not to slip and never stay in alone. If I were you I should occasionally omit a day in order not to do the cure too violently.
—Mozart to his wife, June 11, 1791

Please tell that idiotic fellow Süssmayr to send me my score of the first act [of The Magic Flute], from the introduction to the finale, so that I may orchestrate it. It would be a good thing if he could put it together today and dispatch it by the first coach tomorrow, for I should then have it at noon.
—Mozart to his wife, July 2, 1791

If I go to the piano and sing something out of my opera, I have to stop at once, for this stirs my emotions too deeply.
—Mozart to his wife, July 7, 1791

Franz Xaver Wolfgang Mozart (sometimes referred to as Wolfgang Amadeus Jr.) was born on July 26. He grew up to be a composer and pianist in his own right, and lived in far-off Lemberg (now Lviv, Ukraine) for twenty-five years.

Wolfgang, the father, spent July and August 1791 with intense work on the two operas. On August 26, he left for Prague for the premiere of Tito, set for September 6. Constanze accompanied her husband on the two-day journey, leaving both children, Karl and one-month-old Franz Xaver (presumably in the care of one of her sisters). Franz Xaver Süssmayr, Mozart's student who later completed the Requiem, also came along on the trip. Mozart's early biographers related that just as they were boarding the stagecoach, Mozart was approached by a mysterious stranger who asked him: “And what is going to happen with the Requiem?” (According to the familiar story, Mozart had received a commission from an Austrian aristocrat who didn’t reveal his identity to him, to write a Requiem in memory of the aristocrat’s wife.) Mozart promised that he would get to it as soon as he returned from this important journey.

In La clemenza di Tito, Mozart breathed new life into a type of opera known as opera seria (“serious opera”), already out of fashion by then. Therefore, as early Mozart biographer Franz Xaver Niemetschek reported, “it pleased less in general than its really heavenly music deserved.” The story—a new adaptation of a libretto by star poet Pietro Metastasio that had already been set to music numerous times—was calculated to flatter royalty during the coronation ceremonies: it related how the Roman Emperor Titus forgave Sextus (Sesto) who had attempted to murder him.

The Overture, which Mozart wrote only when the entire opera was already complete (just days before the performance), looks fairly conventional at first glance, with opening fanfare, lyrical secondary theme, development and recapitulation. Yet Mozart at this stage of his career did nothing out of routine, and worked out every detail of the score with incomparable ingenuity, inspiration and technical skill.

Mozart returned to Vienna on September 18, exactly twelve days before the premiere of The Magic Flute. This opera was a completely different affair from Tito: sung in German rather than in Italian, it was no official spectacle but rather popular entertainment. It was performed at the Theater auf der Wieden, outside the city. Theater director and librettist Emanuel Schikaneder, who also sang the role of Papageno, created an exotic fairy tale with a serious philosophical undertone. The protagonist, Prince Tamino, sets out on a quest to rescue Princess Pamina, daughter of the Queen of the Night, from the clutches of the evil sorcerer Sarastro, only to find out that he has been brainwashed by the Queen: it is she who is evil and Sarastro is in reality the High Priest of the Temple of Wisdom. After passing the rigorous tests of silence, fire, and water with the help of his magic flute, Tamino enters Sarastro’s enlightened realm and wins Pamina’s hand as well. Sarastro's world is represented by numerous Masonic symbols (both Mozart and Schikaneder were Freemasons), some borrowed from ancient Egyptian mythology. Yet there is still another layer of meaning to the opera: happiness is not the exclusive realm of those who pass the tests. There is a simpler but equally satisfying form of happiness in store for the bird-catcher Papageno and his bride Papagena. The Magic Flute, then, covers an enormous ground, yet it does so with a grace and a lightness of touch, so that the fairy-tale feel is preserved despite the seriousness of the issues involved.

I have this moment returned from the opera, which was as full as ever. As usual the duet 'Mann und Weib' and Papageno's glockenspiel in Act I had to be repeated and also the trio of the boys in Act II...
—Mozart to his wife, October 7-8, 1791

The overture to the opera begins with some solemn chords (which return later in the opera as symbols of Sarastro’s Temple of Wisdom). Then the tempo speeds up and a section of imitative counterpoint begins. The rhythmically active main theme appears now in a high, now in a low register, until the imitation stops and the full orchestra states the theme. In the middle of the overture, the opening chords return as a reminder of the opera’s serious side, but the music soon resumes its earlier, playful agility and keeps it all the way to the end.

Completing two operas in the space of just a few months clearly took a toll on Mozart's health, and signs of exhaustion soon began to show. The composer appeared to be ill during the visit to Prague; later in September, it was reported that he “sank...into frequent swoons in which he remained for several minutes.” By October, Constanze noticed his “pallor, enervation and weight loss.” He told her about his fear that he was writing the Requiem for himself. Yet he still found the time and energy to compose a sparkling Clarinet Concerto for his friend Anton Stadler, who had also played written some virtuosic solos in Tito.

Stadler had developed a special clarinet with an extended lower register known as the “basset clarinet,” and Mozart originally wrote his concerto for that instrument. It was later adapted for the regular clarinet by an unknown arranger.

Mozart obviously wanted to provide his friend with a piece that showcased the clarinetist's virtuosity, and the famous low notes of his instrument in particular. (There are plenty of those remaining even in the version for regular clarinet.) However, the piece eventually became much more than that; due to its great melodic and formal richness, it occupies a very special place in the composer’s output.

The Clarinet Concerto shares with The Magic Flute a combination of simplicity and sophistication that was, in this form at least, new in Mozart's music. The melodies are as graceful and fresh as ever; yet there are far more grave and serious moments than before. Such moments are characterized by unexpected digressions into minor keys, imitative counterpoint, and—this this is where the low notes of the clarinet become especially important—a darker tone quality. It is a style that had an enormous expressive potential. Despite the total uselessness of such pursuits, one cannot help but wonder about the further style changes Mozart’s music might have undergone had he not contracted his fatal illness in November 1791. What would have happened, had Mozart lived to see Beethoven's arrival in Vienna in 1792; how would their interaction (competition?) have affected the style of each man, Viennese musical life, and music history in general?

The triumphant run of The Magic Flute continued, and Mozart was frequently at the theater, occasionally playing the glockenspiel in the performances when the fancy struck him. Constanze had returned to Baden with the baby, while Karl was sent to a boarding-house in a nearby village.

You should have seen me at supper yesterday! I couldn't find the old tablecloth, so I fished one out as white as a snowdrop, and put in front of me the double candlestick with wax candles...
—Mozart to his wife, October 7-8, 1791

Even during these hectic times, Mozart did not refuse a request from his fellow Freemasons and tossed off Eine kleine Freymaurer-Kantate (“A Little Masonic Cantata,” K. 623) in a matter of days in November.

Scored for male voices (since the Masonic lodges admitted no women), this brief work consists of an opening chorus, repeated at the end. Between the two choruses, there is a recitative and aria for tenor, followed by another recitative and duet for tenor and bass. The text, by one of Mozart's fellow Masons, exhorts the brothers to live a life of wisdom, virtue and good deeds. One feels the proximity of The Magic Flute throughout, but some passages sound uncannily like moments from Haydn's Creation, written seven years after Mozart's death.

If the Clarinet Concerto made us think of a new stylistic beginning for Mozart during the last year of his life, this is true to an even greater extent of the Requiem. In Mozart's swan song, Baroque counterpoint meets an almost Romantic sensitivity, showing that the composer was at the threshold of a new creative period, one cut short by his untimely death.

How much of the Requiem, as we know it from the Süssmayr version, is actually Mozart’s work? Definitely by him are: the first-movement Introit, scored in full the vocal parts and bass line of the Kyrie fugue, most of the Sequence (Dies irae, Tuba mirum, Rex tremendae, Recordare, Confutatis, and the Lacrimosa which breaks off after the eighth measure), as well as the Offertory (Domine Deus and Hostias). The performances this week will consist of only those movements. The Sanctus, Benedictus and Agnus Dei, not performed this week, appear to have been composed entirely by Süssmayr, though Mozart may have played or sung some of the music to his pupil to indicate how he intended it to go.

The most crucial part of the Requiem is the Sequence, which Mozart set as a cantata in six movements, with chorus and solo voices alternating. After the powerful “Dies irae,” the wondrous sound of the trumpet on Judgment Day is represented by a solo trombone (one of the earliest great trombone solos in the literature). Each of the four soloists expresses different feelings about the Day of Wrath before they join together as a quartet. Throughout the sequence, the monumental aspect of the Judgment is expressed by the chorus while the soloists give voice to the anguish of the individual soul. The Sequence culminates in the Lacrimosa—a gripping lament for humanity at the moment when its fate is about to be decided. In the Offertory, Mozart paints the horrors of hell and the attainment of eternal light in equally vivid colors; the promise made to Abraham is represented by a magnificent choral fugue.

According to calculations made by H. C. Robbins Landon, one of the 20^th century's foremost experts on Viennese classicism, Mozart had little more than a month to devote to one of his greatest masterworks. He was fighting ill health almost the entire time, until, on November 20, he took to his bed, with high fever, vomiting, swollen hands and feet that made it difficult if not impossible for him to move. Modern physicians who have examined the spotty evidence available have developed different theories about the exact nature of his illness. Poisoning, either by fellow composer Antonio Salieri (as the persistent rumors would have it) or by someone else, can be safely ruled out. The analysis of Dr. Peter J. Davies, published in 1984, has been by and large accepted by Mozarteans. After reviewing the known facts of Mozart's entire medical history, Dr. Davies concluded that Mozart had contracted a streptococcal infection complicated by the development of Schönlein-Henoch Syndrome, which the dictionary defines as “a disorder that causes the small blood vessels in your skin, joints, intestines and kidneys to become inflamed and bleed.” This caused, Davies wrote, “partial paralysis...due to a cerebral haemorrhage,” in addition to renal failure that led to his death, around 1 a.m. on December 5, 1791. He was buried in an unmarked common grave, after a funeral procession from Mozart's apartment to St. Stephen's Cathedral, where a private ceremony of blessing took place. A benefit concert for the widow and the children was held in at the National Theatre in Prague on December 28. Mozart's hometown of Vienna did not host a similar event until 1794.

Peter Laki