Richard Strauss wrote 'Metamorphosen' after the end of the Second World War, when he was well in his eighties. It's a sort of variations on a theme in reverse - in other words, it ENDS with the theme - taken from Beethoven's Third Symphony. I read this as his attempt to get back to an older Germany, not sullied and dishonoured by Hitler - an attempt I think he knew was futile at that point. One day, perhaps.
The poem pays tribute to him, and to beautiful Bavaria.