SOON after Gustav Mahler died, on May 18, 1911, at the age of fifty, it became known that he had been working on a new symphony at the time of his death. It was clear that he had been unable to complete the work, but there were conflicting reports as to the state in which he had left it, and therefore as to whether it might someday be performed.
In a 1912 lecture Arnold Schoenberg, who was inclined toward numerology, alluded to the fact that neither Beethoven nor Bruckner had been able to get beyond a ninth symphony: "It seems that the Ninth is a limit. He who wants to go beyond it must pass away. It seems as if something might be imparted to us in the Tenth, for which we are not ready." Less mystically but just as pessimistically, Richard Specht, in his 1913 critical biography of Mahler, wrote, "It may be regarded as completely impossible that out of his mute symbols someone else -- no matter how intimately acquainted with Mahler's spirit and essence -- should fashion the full score." Yet where Schoenberg had spoken merely of "sketches," Specht referred to "an eleventh symphonic creation [he counted Das Lied von der Erde in with Mahler's nine numbered symphonies] drafted and completely written down in the short score" -- that is, on several staves, with suggestions for orchestration.
In the years following the First World War, Mahler's reputation steadily rose, especially among younger composers like Schoenberg and his pupils Alban Berg and Anton Webern. In 1920, to celebrate what would have been Mahler's sixtieth birthday, Willem Mengelberg and the Concertgebouw Orchestra, which Mahler had conducted on occasion, staged a Mahler festival in Amsterdam. A few years later Mahler's widow, Alma, decided that the world was ready to learn at least a little about her husband's last symphony.
Mahler had all but completed the scoring of the first movement, and so in 1924 Alma asked her son-in-law, the young composer Ernst Krenek, to touch up the first movement and to score the very brief third movement, which Mahler had titled "Purgatorio." These two movements were performed that October in Vienna under the direction of Franz Schalk, who may also have had a hand in the scoring. That same year Alma published a facsimile edition of Mahler's sketches for the Tenth Symphony. In her preface she wrote, "If at first I held it as my cherished right to preserve the treasure of the Tenth Symphony in secret, so I now know it to be my duty to disclose to the world the last thoughts of the Master."