Short answers, pulled from the story.
Richard Wagner first conceived Tristan und Isolde in 1854, a year that marked a profound shift in his artistic life. He had fled to Zurich after the failed May Revolution of 1849 left him a fugitive with an arrest warrant for his participation in Dresden's uprising.
Arthur Schopenhauer's philosophy triggered what Wagner called ecstatic expression and directly inspired the conception of Tristan und Isolde. Reading The World as Will and Representation by German philosopher Arthur Schopenhauer in 1854 profoundly impacted Wagner and triggered spiritual reassessment.
The work finally premiered on the 10th of June 1865 with Malvina Schnorr von Carolsfeld singing Isolde and her husband Ludwig playing Tristan. The planned premiere on the 15th of May 1865 had to be postponed until Isolde Malvina Schnorr von Carolsfeld recovered from hoarseness.
A typical performance lasts approximately three hours and fifty minutes. Recordings exist going back to 1901 when Mapleson Cylinders captured excerpts during Metropolitan performances until 1930s when recording technology limitations made full opera recordings difficult.
First American performance held at Metropolitan Opera December 1886 conducted by Anton Seidl. Before World War II, Kirsten Flagstad and Lauritz Melchior were considered prime interpreters of lead roles.