It is more poignant for me because this is Dad's birthday, and Strauss died on this same day. In my mind, they are linked together.
But this piece is very interesting, musically speaking. As Beethoven announced the beginning of the romantic era, this was its end - and the start of the modern era. He wrote what is perhaps the culmination of the operatic tradition.
The story of Tristan and Isolde is very old, one of the Troubadour ballads from the High Middle Ages. Tristan is a knight, sent to bring Isolde as a bride to King Mark. Caught at sea in a storm, they drink a love potion, thinking it was a sea sickness cure, and fall madly in love with each other. The love is doomed, and in Gottfried of Strassburg's twelfth century version of the story, one of the travelers with them says, "Tristan, you have drunk your death."
Their doomed love is brought to life by Wagner in his opera, not least because of how he scored the work, and especially the finale here. Liebestod means "Love's death", and it is the Romeo and Juliet simultaneous death scene. Wagner revolutionized opera by his use of harmonic suspension, a repeated refusal to complete unfinished themes. This refusal builds tension which is only released at the final, lyrical completion. This particular scene is striking in how you hear the suspension from the very beginning of the video, and how it allows a very subdued final chord to be magnificent. It takes a full six minutes to reach the "aha" moment where the theme resolves, which makes the resolution even more sweet.
Mom and Dad took me to hear this (they had season tickets to the Symphony). I'd never heard it before, and it led to a memorable chat with Dad about Gottfried von Strassburg, Schopenhauer, inflection points in music, and how they're all bound up in this music. I sure miss those.
Happy birthday, Dad. I sure miss you.