October 1814. Napoleon had retreated from Moscow, abdicated and gone off to Elba. In Vienna, Schubert was feverishly composing songs at the rate of at least two a day. On October 19th, he wrote Gretchen am Spinnrade. And the rest - for six weeks - was silence. Having written Gretchen, it was as if he drew back from the abyss, alarmed at what he had begun. Graham Johnson is convinced that this was for Schubert an epiphany of his own genius. "And he was simply dazzled by it." Schubert, and the Lied itself, was never to be the same again. His own swan-song, Die Taubenpost, was to come only 13 years later, but in the wake of 600 Lieder, 18 stage works, 45 pieces of church music, and more than 100 cantatas, choruses and part-songs.

Schubert's relationship with the human voice was unique in his output: he was, indeed, the fons et origo of an art form which was to rise to pre-eminence in his lifetime. And the reasons for this were manifold. Brian Newbould, in his study of Schubert, The Music and the Man (Gollancz: 1997), has rightly emphasized the importance to Schubert of an existing musical lingua franca, "based on an orderly system of tonality providing an ever-present reference point against which harmonically conceived melody achieved clarity, coherence and musical meaning." "The underlying modus parlandi," he writes, "had such a logic and energy of its own that one could speak it - like one's native verbal language - as second nature."

And if Schubert was born at exactly the right time for the human voice to rise from speech to song in a glorious efflorescence, then he was also born in the right place. The daily life of Schubert's Vienna, despite being ravaged by the winds of international politics, and oppressed by Metternich's police state, was characterized by what Johnson has described as "a miraculous combination of creativity and sociability which is without parallel in the history of music". The domestic literary and musical gatherings, and the Bildung circles which met for the purpose of self-improvement and education, provided not only the stimulus but the emotional support and warm companionship vital to Schubert's own creativity. His growing self-confidence was bolstered by the talents of friends and contemporaries who included the poets Mayrhofer, Stadler, Schober and Collin.

Across the border, the poetry of Goethe, Heine and Schiller, of Schlegel, Hölty and Rellstab was rolling hot off the presses, bringing with it imagery from a natural world 'known' by ears which, not yet blunted by the roar of the infernal machine, were keenly alert to the movement of wind and water; and eyes, as yet undulled by the light pollution of electricity, which were still awed by the luminescence of moon and stars. Tracking the body's natural rhythms, were metres in which music could, in its turn, re-create the steady motion of human footfall, a trotting horse, a racing pulse, a rushing millstream. What is more, Schubert's lack of success in opera - to which we shall return – meant that all these stimuli were to be channelled into song: the only part of his oeuvre in which he was never to know the frustration of failed performance. Almost every song Schubert wrote was performed at least once in his lifetime.

There was, of course, life and song before Gretchen - even before Schubert's own first song, Hagars Klage, written when he was 14. The predecessors of the romantic Lied, the North German ballads of composers like Johann Friedrich Reichardt, Carl Friedrich ZeIter and Johann Rudolph Zumsteeg, were good enough to stimulate the young Schubert without being great enough to intimidate him.

Schubert's earliest songs and ballads, with their ears wide open to the melodies of Italian opera, and with their deftly imaginative piano writing, show the nature of the alchemy which was already at work.

Dietrich Fischer-Dieskau's pioneering work in recording almost the entire repertoire over a period of 15 years - for him "a story with no ending" - began to reveal what was going on. In the Hyperion Complete Edition Graham Johnson was to reach those parts which even Fischer-Dieskau had disdained, illuminating the unique qualities of the shortest, most naive ditties, or the most (over-)extended ballad and melodrama.

Elly Ameling, in Vol 7, was to be charged with Minona, oder die Kunde der Dogge, and the modest Naturgenuss, totally ignored by commentators such as Einstein and Richard Capell. Marie McLaughlin, in Vol 13, brought Edward, Edward out of the Celtic twilight where it had been temporarily eclipsed by Carl Loewe's setting. And Peter Schreier, in Vol 18, was to reveal how Schubert changed the face of the simple strophic song forever.

At the start of the Hyperion project, Johnson determined to include at least one little-known ballad on each disc. Now, little by little, these works are beginning to make themselves heard on the concert platform too. "In order to understand the very greatest of Schubert's songs," Johnson told me ten years ago, "we must know and perform the rest. Sometimes his plainer children have been neglected at the expense of his more obviously beautiful creations. It isn't that he loves them less, or gave them less. He just decides when melody is more important than prosody and declamation, and when it is not. He rations out melody as something to be used with discretion. What is appropriate for a great Goethe lyric may not be apt for a more homely one by Mayrhofer. We have to trust Schubert."

Johnson would argue - unlike Elizabeth Norman Mackay in her biography - that Schubert's is not the creativity of a manic-depressive. "His inspiration doesn't come and go in waves, as it did with Hugo Wolf, for instance. No: there's a continuous creativity, looking after the various regions of song. He admired the North German school of Reichardt where shying away from prodigal melodic invention was considered better form. You didn't try and upstage the words: you just set them so that they could he heard - and hit the heart."

Not only has the Schubert song canon expanded in the last half century, but the songs are now approached by performers and listeners alike with fewer preconceptions and ever-changing expectations. Brigitte Fassbaender, who has made her own considerable contribution to the growth of tbe repertoire, is thrilled that the new generation of singers is eager "to discover the unknown Schubert. A young tenor called Lothar Odinius recently gave a whole evening of relatively unknown strophic songs. And the public was so enthusiastic! I sense too that there is a new type of respect for Schubert. Young singers are working in a very self-aware way - in dialogue, as it were, with the public, rather than treating the recital as some sort of holy event. It is for them a part of daily life - full of life, full of love - everything Schubert wanted!"

Graham Johnson, too , picks up on "a new sense of deference to the score - and a real sense of awe. Young singers are asking what they can do for this music, rather than what it can do for them. Even in gigantic performing personalities, with huge fantasy, like Matthias Gorne, there's a sense of modesty." Johnson is acutely aware, too, of the often subconscious influence, over the last 30 years, of the early music movement.

"Singers of Fischer-Dieskau's generation knew a Viennese Schubert. The distance between him and Brahms was perhaps not as great for them as we feel it to be now. We hear tempos that are faster, articulation which is cleaner. Even in the playing of Gerald Moore, we hear less and less pedal. And then we get to Charles Rosen who states unequivocally in The Romantic Generation (HarperCollins: 1995) that, until 1830, the pedal was used entirely for colour and atmosphere - not to connect the movement of the fingers". Johnson, of course, rejects the dogma of authenticity-solely-through-the-fortepiano. 'That belonged to 20 years ago." But he acknowledges the assimilation, as if by osmosis, of its particular timbre and strength. He plays increasingly with the lid up, "to create more clarity and more brilliance..."

Nowhere are the shifts in performance practise more sharply focused than in the song-cycles. The sophisticated stylization behind the simplicity of Wilhelm Müller's verse in Die schöne Müllerin stimulated Schubert to compose what Johnson has called a "highly-wrought parable". After more than 37 recordings, the cycle continues to drive a mill-race of commentary and criticism.

As early as 1979, Johnson and his Songmakers had reinstated into one of their live performances the poems by Muller which Schubert had not set - if only for the opportunity this afforded for some respite in a cycle even more exhausting to perform than Winterreise. Fassbaender's was the first recording to include a reading of the unset poems in between the songs. The practice, later taken up in the Hyperion Edition when Fischer-Dieskau read and Ian Bostridge sang, was important to Fassbaender in helping her find the right tone.

"When you look closely at the spoken Prologue and Epilogue, you realize the sense of irony in the work. You begin to understand that it is playful too." The establishing of a tone, a register, was particularly necessary for Fassbaender as the first woman to have performed the cycle complete. "Of course it is meant for a tenor, and the rapid fluctuations in mood which belong to an adolescent male. It is hard for a woman to identify with that world. This was the greatest challenge of all to me: greater than either Schwanengesang or Winterreise.

"Winterreise's themes of love and death, after all, have the same meaning for a woman and for a man. Though it takes everything from you; and if you're not prepared to give everything, then you shouldn't sing it. As a woman, I always start with a certain sense of distance, of abstraction from the persona of Winterreise. But it doesn't last. After the fifth song, I'm deeply involved. And for me, this is not the experience of a young man. It seems to me the desperation of a mature person. I can 't understand how young singers start so early with Winterreise..."

Christa Ludwig was one of the first women to sing Winterreise in its entirety, after Lotte Lehmann, and after extracts recorded by Elena Gerhardt, Maria Ivogün, Elisabeth Schumann and Kathleen Ferrier. Ludwig chose Winterreise for a remarkable farewell recital at the Wigmore Hall in October 1993 and, within a still perfectly controlled contour of line and tone, conveyed the torture of ever-present pain within a sense of existence outside time. Earlier she had told me: "You grow into Winterreise, passing through its different stations in a search for tranquillity. When we reach 'Der Leiermann' at the end, we are faced with the Wheel of Life, turning on and on with no end. The question 'Shall I go with you?' expresses the same desire as in Mahler's 'Ich bin der Welt abhanden gekommen'. We are into Nirvana, into a space where nothing counts any more. There is no question of woman or man."

Even within the male experience of Winterreise, more than 60 years of recording have revealed an extraordinary range of responses. As distances and levels of recession shift between performer, persona, and those resonant emblems of the weathervane, the crow, the charcoal burner, the organ-grinder, so there has been a journey through the attitudes of romantic heroism, psychopathological intensity, and on to stoicism and ironic distance. Ian Bostridge is preoccupied with precisely this dilemma of distance.

"It's very difficult to sort out to what extent the singer becomes the persona, or is a commentator. Each time I find one's integration with the text changes. At the moment I feel there's a sort of Heine-like protagonist. When Schubert responds to Müller's deliberately ludicrous imagery, he emphasizes the fact that it is used self-consciously - in 'Der Krahe', for instance. The recognition of self-deception is very important. This persona is self-knowing. And in singing Winterreise, you're mimicking the process the protagonist himself is going through. You're being self-obsessed in performing the cycle! I remember something Fischer-Dieskau wrote in one of his record notes. He asked whether this was a cycle we really ought, morally, to perform in public at all..."

Winterreise certainly continues to provoke extreme reactions. In 1983 David Wilson-Johnson and David Owen Norris decided that we had really got it all wrong: Winterreise should exist as a cycle of songs sung in the poet's own ordering, not that in which the songs were finally published. Wilhelm Müller published his first 12 poems in 1823, and Schubert set what he thought to be a complete cycle. He then discovered that Müller had later published 12 more poems, some of which were interspersed between the lyrics he had already set. If Schubert had wished his first part to correlate with Müller's, he would have had to interpolate four new poems: ("Die Post", "Der greise Kopf', "Die Krahe" and "Letzte Hoffnung"). And he would have had to shift four songs already composed into the (as yet uncomposed) second half. Schubert did not make such a last-minute revision; and Graham Johnson argues cogently, in The Songmakers' Almanac: Reflections and Commentaries (Thames Publishing: 1996), why it was that Schubert did not "retrace his steps, pick up the baggage of which he has already divested himself, and transport it to new realms, where it had no place". Schubert instead began his second part with the unset poems, and went on to the end, omitting the poems he had already composed.

Wilson-Johnson, though, feels that Müller's order reveals a stronger, more consistent story line, a significantly changed character. "This is a man very much in control of his fate. He's afraid of commitment. He likes the open-air life, the force of the elements. He's never so happy as when there's a storm brewing. He's aware of his own image and, in songs like 'Letzte Hoffnung', pokes fun at it. This character is firmly established in the first 12 songs, and Müller rearranged the complete cycle to reinforce it. The publisher then made nonsense of the arrangement. If, for instance, you move from the exhilaration in the storm in 'Einsamkeit' straight on to 'Mut' you have an astonishing juxtaposition. There is a more aware, assertive, aggressive character..." 

Wilson-Johnson's wanderings seem only gently aberrant in the light of Hans Zender's peregrination. In the autumn of 1994 in London's Queen Elizabeth Hall (and a year later on disc: RCA, 9/95), Zender presented a "composed interpretation" of Winterreise: a re-creation which, he claimed, did no more than take a characteristic set of responses - in matters of tempo, transposition, nuancing - to their 'logical conclusion.

In grafting on to Winterreise an introduction and bridge passages, and in transforming Schubert's "sound ciphers" into overt sound effects in the throats and instruments of Ensemble Modern, Zender's recomposition ranged from an act of virtuoso imagination to the banal. He flashed back to the Biedermeier and fast-forwarded to Bruckner, Wolf and Mahler - and all in order "to reinvigorate the initial impulse, the existential force of Schubert's original".

It had to be only a matter of time before Winterreise was fully staged. A year later Hans Peter Cloos brought his Opera Comique 'production' of Winterreise to London, and Martyn Hill, with a little help from an installation by Christian Boltanski and the ghostly choreographed presence of a pair of Polish twins, set out on his journey - along a particularly sinister stretch of German railway track...As Benjamin Britten said, on the occasion of receiving the Aspen Award, "Every time I come back to Winterreise, I am amazed not only by the extraordinary mastery of it...but by the renewal of the magic: each time the mystery remains... "

The Doppelgänger installation cannot be far away. Curiosity in the cryptic significance of Schubert's most chilling Schwanengesang has been kindled by observations in Werner Aderhold's notes to the recording of Schubert's Masses by Bruno Weil (Sony Classical, 5/97). He points out that Schubert reused what he sees as the cruciform C-B-E nat-D motif from "Der Doppelganger" in the Agnus Dei of the E flat Mass - for "a man stands there too and stares aloft, and wrings his hands in an excess of grief..."

Brigitte Fassbaender is intrigued but bewildered by the 'cross' reference. "I feel the motif was simply there in Schubert's subconscious. He often wrote in a trance - we know that - and afterwards he could barely recognize what he had written. I don't honestly feel it matters from the point of view of interpretation. 'Der Doppelgänger' comes from a schizophrenic mind, and is one of Schubert's most modern songs. For me, Schubert has never been a romantic composer: I would call him a 'classic expressionist'. His music points out far into the music of our century. And I always wanted to perform him in such a way that we can understand him with our feelings."

If the solo Lied was never to be the same again - and Bostridge feels that, in the very act of composing his cycle, Schubert was making a statement about the new pre-eminence of song - then neither, indeed, was the partsong, in its metamorphosis from sentimental homespun, or rumbustious tavern-song, to an artefact of extraordinary sentience and sophistication. No one is more acutely aware of this than Graham Johnson who has done so much to reactivate, against all odds, the creative spirit of Schubert's own time.

The part-song grew from the Lieder-Tafel of late 16th- and 17th-century Germany, in which camaraderie and alcohol would mingle in taverns and coffee-houses. "By Schubert's time," says Johnson, "it was far less of a spontaneous activity. But there was a craze for four-part songs in Vienna, and he was asked to write them again and again. He got sick and tired of it: he knew there was a limit to the medium. But he poured himself into them - as he did with everything he wrote. There are no short cuts in Schubert."

The Hyperion Complete Edition is rowdy with the patriotic songs and choruses which are Schubert's tribute to his poet-friend Theodor Körner who died at 22 on the battlefield of Gadesbusch in North Germany, fighting with the Lutzow volunteers. "The aggressive soldier-boy of the Leyer und Schwert ('Lyre and Sword') settings", wrote Johnson, "is Schubert himself as an adolescent Walter Mitty." And Vol 22 bubbles with the early Trinklied, Punschlied and Lob des Tokayers, the latter written in August 1815, a musical evocation of that fragrant late-summer glow which can still be experienced in the small, vine-garlanded border villages of the Neusiedlersee.

And then, suddenly, the exquisite Das Leben ist ein Traum, D269, one of two three-part choral settings with piano, each voice drifting in and out of the consciousness of the other. And the five virtually unknown settings of Das Grab, one of the poems which meant most to Schubert, and which he set for male quartet, unison male chorus and four unaccompanied parts. The starry cover of Hyperion's Vol 26, with its 1826 Schubertiad, encloses the haunting Seidl chorale, Grab und Mond (D893), prefiguring the dark ambivalence of the late solo Heine settings. And then the Nachthelle (D892) which tracks the stars in their courses, as a high, silvery tenor who haunts so many of the partsongs (and was undoubtedly Schubert's friend Ludwig Tietze) rises above a gently echoing chorus. Listening to Nachthelle, reflects Johnson, "is like watching a young god at play, rearranging the constellations for pure pleasure".

More wonders are to be disclosed in Hyperion Vol 28, released as an 1821-2 Schubertiad. For Johnson made an exciting discovery of his own. "Let me show you something!" He crosses his study and returns with a long, slim album of heavy, fragrant paper, exquisitely bound. "This is the music-book of Johann Karl Unger, professor in the history of law at the Theresien-Academy in Vienna. He recommended Schubert as a tutor for the Esterházys in Zseliz. His daughter, Karoline, was the first mezzo in Beethoven's Ninth, and Schubert taught her the role of Dorabella. Nice old boy - and something of a poet and composer too. What an indication of the culture of Vienna at that time: that someone who was not a professional musician should have taken such pride in making his own musicbook!" Johnson turns the crisp pages to a song called Die Nachtigall, its dactylic rhythms dancing over the pages and issuing in a black stream of trilling notes. "Well, Schubert saw the poem in this very book, and made his own setting of it for male quartet. I'll play it for you..."

It was precisely the Schubert of the Schubertiad - the convivial musician, loyal companion, warm and often naive friend - who was to be at odds with Schubert the opera composer. Although it was undoubtedly his visits to the opera which inspired him to start writing Lieder at all, and although it was his dearest ambition to be recognized as an opera composer, Schubert surely lacked the entrepreneurial steel, the pragmatism, the energetic drive for self-promotion, vital then as now in making a career in the theatre. At the premiere of his one-act farce Die Zwillingsbrüder (D647), the only one of his operas he ever saw staged, Schubert, embarrassed by the loud support of his friends, refused to take a bow, and his baritone friend Johann Michael Vogl had to announce from the stage that the composer was absent. When the opera fell out of the repertoire after six performances, Schubert, typically, made no attempt to revise the score or to raise further interest in the work.

There are plenty of frequently rehearsed reasons for Schubert's lack of success in opera: a paucity of good librettists, a court theatre in dire financial and artistic straits; and, as Brian Newbould has shrewdly observed, the fact that Schubert was moving consistently towards an ever more epigrammatic means of expression in his writing as a whole. Drama was being distilled into song: András Schiff has famously commented that for him there is more drama in Die junge Nonne than in the whole of The Ring. By 1828 Schubert's stage was Auf dem Strom; his theatre was the landscape of The Shepherd on the Rock. In short, Schubert did not need opera.

Yet, as Elizabeth Norman Mackay points out, his operatic scores reveal that he was in the very forefront of the development of music theatre, way ahead of his contemporaries, "creating forms and orchestral sounds which anticipated the musical world of Wagner". Fischer-Dieskau went as far as to say that Wagner actually came too early. Were it not for him, Schubert would have had a much more profound influence on the 19th century.

Schubert's vocal writing constantly erupts with operas-manques - from the melodramas of Ossian, to the dramatic scenae from Faust, to the Heine settings of Schwanengesang, and on to Der Hirt auf dem Felsen and Auf dem Strom. The finest example of Schubert's innovative drama-in-music, though, is surely Lazarus. Such is the visionary quality of its musical invention that Brian Newbould, puzzling like many before him on the significance of its unfinished state, was moved to ask, "how does one play the game through to a successful conclusion when the goalposts have just been moved?"

Schubert's Lazarus knows no resurrection. For the three-act poem by Niemayer on the death, burial and resurrection of Lazarus, Schubert provides only a first act and part of the second - all in an extraordinarily pliable and expressive arioso which points far ahead to the through-composed operas of the late-19th century. Einstein claimed that Lazarus surpassed both Tannhaüser and Lohengrin as music drama. Edison Denisov's completion of Lazarus at Helmut Rilling's suggestion (Hanssler Classic, 4/97) makes no attempt at stylistic continuity. In RW's words this is Schubert "refracted through a 20th-century prism": the light spectrum radiates in the shifting colours of post-Mahlerian expressionism, 12-tone writing, and bold rhythms and orchestration.

Above all, Lazarus has taunted scholars with teasing metaphysical questions as to the possible reasons for Schubert's abandoning the work. Was he, perhaps, unconvinced - or daunted - by the concept of resurrection itself? Aha, they cry; and no resurrectionem mortuorum at the end of the Credo in Schubert's Masses either! Scholars have been muttering for years about Schubert's excision of certain liturgical Father/Son relationships, and references to one Holy, Catholic and Apostolic Church. The arguments about whether Schubert was acting as pragmatist, practical musician, wounded son, amateur theologian or esoteric mystic turn and turn again. But for Wolfgang Sawallisch, who has recorded all the church music, one thing is sure. The Masses, he believes, show a harmonic depth and sense of experiment unique in Schubert's oeuvre, and comparable to the visionary daring within the sacred works of Beethoven and Bruckner.

Schubert's church works, though, should not be confused with his sacred works. "I have never," wrote Schubert, "forced devotion in myself." When it comes over him unawares then, he knows, "it is usually the right and true devotion". And , of course, it is constantly, continuously, coming over him unawares. Die Götter Griechenlands provided Schubert with yet another Pantheon. And the countryside which spread out around him, and resonated in his soul through the neo-Platonic Romanticism of contemporary poets, created for him a theology of immanence. Das Lied im Grünen was written during Schubert's last period of bucolic refreshment; Die AIlmacht emanates the fragrance of his Steyr holiday of 1825. In Ganymed spiritual ecstasy reaches its apotheosis.

Those with ears to hear will surely sense in the last lines of Die schöne Müllerin and Der Hirt auf dem Felsen - that broad blue sky. and that renewal of the soul's wandering in another ever-renewing spring - the reverberations of another resounding soul and soul-mate who, similarly, fears no more the heat o' the sun. Graham Johnson has the last word. "What I didn't know, when I began the Hyperion Edition - and I do know now - is that Schubert is as great a songwriter as Shakespeare is a playwright. Because, of all the Lieder composers, he is the one who is infinitely adaptable in performance to every different human being. Just as Shakespeare is infinitely flexible in the type of productions he can receive. All the singers I have ever worked with have a Schubert which is true to each one of them. His music contains multitudes... "

This article originally appeared in the June 1997 issue of Gramophone. To find out more about subscribing the Gramophone, please visit: gramophone.co.uk/subscribe