Since 1956, the Mozart Week, celebrated in Salzburg each year around the composer's birthday, has been the first festival of the year. Nikolaus Harnoncourt's polarizing debut concert in 1980 uniquely reflects the mission of the International Mozarteum Foundation to offer the broadest possible, ever new spectrum of Mozart interpretations.
At that time, the greater part of the public and critics still paid homage to another titan. On February 1, 1980, Karl Böhm conducted the triad of the three late symphonies in E-flat major, K 543, G minor, K 550, and C major, K 551. It was his last performance at the Mozart Week, for he died in Salzburg on August 14, 1981, shortly before his 87th birthday, in the midst of rehearsals for Richard Strauss’ Elektra. In honest enthusiasm and carried by the approval of the audience, Nikolaus Schaffer of the Salzburger Volkszeitung wrote about Böhm's swan song: “If there is such a thing as a ‘philosopher's stone’ in music, Karl Böhm found it in his Mozart interpretations. What else can  one say about such a concert except that Karl Böhm has once again paid homage to Mozart in an incomparable way. [...] Delicacy and relentlessness, grace and deep seriousness, agility and calmness - yes, above all this all-pervading calmness is emotional delight - are no opposites here.”
Three days earlier, on Januarg 29,1980, Nikolaus Harnoncourt had introduced himself to the participants of the Mozart Week with the Concertgebouw Orchestra and its then solo oboist Werner Herbers in the Grosses Festspielhaus in Salzburg with completely different interpretive principles. At first, the program composition did not suggest any sensation. With an overture, an instrumental concerto, and two mature symphonies, one was supposedly on the safe side. Nevertheless, the development section of the overture to The Magic Flute at the latest made one prick up one's yars: Harnoncourt did not want to believe in the operetta bliss of a suburban farce, and here, already, he showed rugged abysses.
For the attentive audience, of course, the curtain did not just rise for Harnoncourt with the three wind chords at the beginning of the overture, for the program had unusually given him the opportunity to explain his artistic credo under the title "On Notation and Articulation in Mozart". Today, the two-page text reads smoothly and, in many respects, familiarly, a sign that Harnoncourt's persistent talk about music as sound speech and about traditions ofthe unwritten in Mozart's music and has not gone unheard. In 1980, however, this text represented a radical position. How is it, Harnoncourt asks, that a piece sounds completely different in different interpretations, and in some cases is no longer recognizable at all?
For Harnoncourt, the main reason for this is articulation. Originally, articulation only had to be notated where the composer deliberately wanted to deviate from the - now veiled - norms of musical usage. Passages that the composer left without articulation or dynamics are therefore not to be played in an undifferentiated manner, but rather it is necessary to rediscover these lost self-evident elements. The recording of a public rehearsal with the Mozarteum Orchestra from the Mozart Year 2006 vividly explains how Harnoncourt tries to decipher Mozart's intentions from his sparse indications of articulation in the original manuscripts.
In this fascinating sound document, it also becomes clear how important the relationship between main voices and accompaniment was to Harnoncourt. In the prevailing performance tradition of the time, the accompaniment was unconditionally subordinated to the beauty of the melody. The rehearsal recording shows how the conductor, on the other hand, sensitized the musicians to the fact that Mozart repeatedly drew on traditions of dance music: The accents are then often in the bass, while other instruments softly play the off beats.  On this always audible foundation, the melodies can then unfold freely.
How massively articulation and shaping of the accompanying figures change  the character of a work is perhaps nowhere more evident than in the recording of the Oboe Concerto, K 314. Where would one have heard the beginning of the first movement so march-like, where the couplets of the rondo movement so rustic? Karl Löbl, the reviewer for the Kurier, understood the intentions - and yet was deeply disturbed: “Werner Herbers, together with Harnoncourt, had worked out a phrasing that quite  deliberately went against Mozart's natural melodic flow."
The same is true of Harnoncourt's interpretation of the Symphony in C major, K 338. Another one of Harnoncourt's trademarks is striking here: the pointed sounds of the horns, trumpets, and timpani, that cancel out the usual beautiful sound. This stylistic device also plays an important role in the rehearsal recording of the Symphony in G minor, K 183.
Finally, the interpretation of the ‘Haffner' Symphony, K 385, turns the spotlight on yet another of the conductor's favorite themes, tempo. Harnoncourt was convinced that few composers were so concerned and  anxious to express their ideas and wishes through similarly differentiated tempo markings. Harnoncourt therefore follows exactly Mozart's instructions in the letter to his father ofAugust 7, 1782: “The first Allegro must be quite fiery. Exactely - the last - as fast as it is possible.”
The overall judgment of the public and the press at the time was ambivalent. Wolf-Eberhard von Lewinski of the Süddeutsche Zeitung spoke of an evening “worthy of note" and rightly stated that  the “last word on Harnoncourt's view of Mozart has not yet been spoken”; damning reviews were countered by equally pathetic hymns of praise.
Nikolaus Harnoncourt deserves credit for having made historical performance practice respectable in Salzburg. The memorable debut concert of 1980 was the prelude to a long success story that culminated with the Mozart Week 2006, when Nikolaus Harnoncourt was Artist in Residence and gave his  acclaimed ceremonial address on January 27 on the 250th birthday of Wolfgang Amadé Mozart.