Keeping track of how appreciation and understanding of Tristan und Isolde has evolved, in live performance, recording and scholarly studies, is a formidable task. One path through the labyrinth is opened up by Wagner’s poetic text, in which the title characters express their disorientation, their alienation from communal norms. Stage directors and musicological commentators alike have found ways of dramatising the particular tensions between conformity and nonconformity that encapsulate the drama’s representations of love and death, in settings that balance magical interventions (the love potion) against the worldly intrusions of King Marke and his entourage. Surveying and critiquing accounts of the role that Tristan und Isolde has played at the heart of fundamental changes to musical form and style since the 1860s reinforces the value of arguing that the continued presence of modernist qualities in contemporary music – works by Schoenberg, Nono, Henze, Andriessen and Anderson are instanced - is a direct consequence of Wagner’s materials and methods, particularly in Tristan.

Mahler’s influence among composers intensified steadily over the course of the twentieth century. Within the Austro-German orbit, his impact is evident in the music of figures as varied as Kurt Weill, Hans Werner Henze, and Dieter Schnebel. Further afield, by the mid-1920s a distinguished array of composers including Aaron Copland and Dimitri Shostakovich had begun to engage seriously with Mahler’s music. This trend would continue in the second half of the twentieth century, with the renewed attention paid to Mahler outside Central Europe giving rise to an even more diverse group of followers, including those eager to find emancipation from some of the more influential strands of postwar modernism: George Crumb, George Rochberg, Luciano Berio, Luigi Nono, Pierre Boulez, Peter Maxwell Davies, Michael Finnissy, and Jonathan Harvey. These are surveyed here with particular attention to the diverse ways in which Mahler’s influence expressed itself.