Cosima's diary - Sunday, 25 December 1870
About this day, my children, I can tell you nothing-nothing about my feelings, nothing about my mood, nothing, nothing. I shall just tell you, drily and plainly, what happened. When I woke up I heard a sound, it grew ever louder, I could no longer imagine myself in a dream, music was sounding, and what music! After it had died away, R. came in to me with the five children and put into my hands the score of his Symphonic Birthday Greeting. I was in tears, but so, too, was the whole household; R. had set up his orchestra on the stairs and thus consecrated our Tribschen forever! The Tribschen Idyll—thus the work is called. — At midday Dr. Sulzer arrived, surely the most important of R.'s friends! After breakfast the orchestra again assembled, and now once again the Idyll was heard in the lower apartment, moving us all profoundly (Countess B. was also there, on my invitation); after it the Lohengrin wedding procession, Beethoven's Septet, and, to end with, once more the work of which I shall never hear enough! — Now at last I understood all R.'s working in secret, also dear Richter's trumpet (he blazed out the Siegfried theme splendidly and had learned the trumpet especially to do it), which had won him many admonishments from me. "Now let me die," I exclaimed to R. "It would be easier to die for me than to live for me," he replied. In the evening R. reads his Meistersinger to Dr. Sulzer, who did not know it; and I take as much delight in it as if it were something completely new. This makes R. say, "I wanted to read Sulzer Die Meistersinger, and it turned into a dialogue between us two."
The Siegfried Idyll is a symphonic poem for chamber orchestra, composed by Richard Wagner as a birthday present to Cosima, after the birth of their son Siegfried in 1869. It was first performed on Christmas morning, 25 December 1870, by a small ensemble on the stairs of their villa at Tribschen. Wagner's opera Siegfried, which was premiered in 1876, incorporates music from the Idyll. It was once thought that the Idyll borrowed musical ideas intended for the opera, but it is now known that the opposite is the case: Wagner adapted melodic material from an unfinished chamber piece in the Idyll and later incorporated it into the love scene (Ewig war ich) between Siegfried and Brünnhilde in the opera.