Hans Werner Henze's output is primarily dominated by large-scale, representative musical genres with a richly differentiated instrumental tonal palette: opera and other forms of musical theatre works, ballet, solo concertos and cantatas and also music for large-scale orchestra or chamber ensemble. In contrast, the chamber music works which Henze has composed throughout his entire compositional career right up to the present day have always remained somewhat on the sidelines. Many of these chamber music works had been composed for specific occasions, chiefly to honour figures who had accompanied him on longer or shorter stretches of his journey through life.

Henze composed An Brenton in July 1993 for an event commemorating the Australian violinist Brenton Langbein who had just died. The violinist had been a long-standing leader of the Collegium Musicum Zurich, the orchestra established and conducted by Paul Sacher, and was subsequently also the leader of the Basel Chamber Orchestra [Basler Kammerorchester].He additionally held a violin class at the Music Academy in Basel for a substantial period of his career. Interestingly enough, this piece is not composed for the violinist's instrument, but instead for solo viola. The work was given its first performance on 15 July 1993 by Jurg Dahler, one of the two viola players of the Chamber Musicians of Zurich [KammermusikerZurich]. This ensemble had been formed by Langbein in 1962: it frequently included compositions by Henze in its programmes and had given the premiere of Henze's music for Volker Schlondorffs Film Der junge Torless in its transformation as the Fantasia of the same name for string sextet (1967) in 1968. Langbein was the soloist in the first performance of Henze's Violin Concerto No. 2 in 1972 which had been commissioned by Paul Sacher. Henze had already made acquaintance with Langbein during the 1960s.