The libretto for Henry Purcell's Dido und Aeneas was written by the English poet and writer Nahum Tate (1652-1715), who based his text on his own play, the tragedy Brutus of Alba or The Enchanted Lovers from 1678, which in turn takes motifs from the fourth canto of the unfinished epic poem Aeneid by Virgil (70-19 B.C.). Approximately 220 years later, in the summer of 1909, Arnold Schönberg was introduced to the aspiring Viennese physician Marie Pappenheim. Under the pseudonym Maria Heim, she had made a name for herself as an author of poetry. The idea for a stage play most likely arose in a joint conversation; Pappenheim wrote the text for Expectation in a few days: "I wrote lying in the grass with pencil on large sheets of paper, had no copy, hardly read through what I had written."

Dido und Aeneas is the first complete stage work by the 30-year-old Henry Purcell - and the only one to bear the genre title "An Opera". There was no independent operatic tradition in England at the time: Dido und Aeneas is an innovative, singular work in the history of European and English opera, with no direct predecessors or successors. Purcell fused influences from the Italian, French, and English stage traditions into a form all his own, condensing the narrative into just one hour. In his music, the dramatic dominates, the affects and emotions of the characters and situations of the terse plot stand in the foreground over pure vocal virtuosity.
Arnold Schoenberg also places his composition entirely in the service of the dramatic plot, albeit in a very different way: in completely free tonality, Schoenberg has the large-scale late-romantic orchestra trace the states of a woman's soul: "In the Erwartung, it is the intention to depict what takes place in a second of the highest mental excitement, as it were with slow motion, extended to half an hour." Arnold Schoenberg set Pappenheim's text to music in only 17 days between August 27 and September 12, 1909.

The history of the composition and premiere of Dido und Aeneas is convoluted and ambiguous. It is certain that Purcell's Dido was performed in Chelsea in 1689 under the direction of Josias Priest, the famous ballet master of the time. It is likely, however, that the opera was first performed some time earlier, either around 1684 at the court of Charles II, around 1687 at the court of James II, or around the time of the accession of William III and Mary II to the throne in 1689. The monodrama Expectation was not premiered until 15 years after the composition was completed: Numerous attempts at an earlier performance by Schoenberg had failed. Alexander von Zemlinsky finally put it on the program of the Music Festival of the International Society for New Music in Prague on June 6, 1924. After the premiere, Anton Webern wrote about an "unheard-of event: in it, all traditional architectonics have been broken.