Dietrich Fischer-Dieskau, the German baritone whose beautiful voice and mastery of technique made him the 20th century’s pre-eminent interpreter of art songs, died on Friday at his home in Bavaria. He was 86.


His wife, the soprano Julia Varady, confirmed his death to the German press agency DPA.


Mr. Fischer-Dieskau was by virtual acclamation one of the world’s great singers from the 1940s to his official retirement in 1992, and an influential teacher and orchestra conductor for many years thereafter.


He was also a formidable industry, making hundreds of recordings that pretty much set the modern standard for performances of lieder, the musical settings of poems first popular in the 18th and 19th centuries. His output included the many hundreds of Schubert songs appropriate for the male voice, the songs and song cycles of Schumann and Brahms, and those of later composers like Mahler, Shostakovich and Hugo Wolf. He won two Grammy Awards, in 1971 for Schubert lieder and in 1973 for Brahms’s “Die Schöne Magelone.”


Mr. Fischer-Dieskau had sufficient power for the concert hall, and for substantial roles in his parallel career as a star of European opera houses. But he was essentially a lyrical, introspective singer whose effect on listeners was not to nail them to their seatbacks, but rather to draw them into the very heart of song.


The pianist Gerald Moore, who accompanied many great artists of the postwar decades, said Mr. Fischer-Dieskau had a flawless sense of rhythm and “one of the most remarkable voices in history — honeyed and suavely expressive.” Onstage, he projected a masculine sensitivity informed by a cultivated upbringing and by dispiriting losses in World War II: the destruction of his family home, the death of his feeble brother in a Nazi institution, induction into the Wehrmacht when he had scarcely begun his voice studies at the Berlin Conservatory.


His performances eluded easy description. Where reviewers could get the essence of a Pavarotti appearance in a phrase (the glories of a true Italian tenor!), a Fischer-Dieskau recital was akin to a magic show, with seamless shifts in dynamics and infinite shadings of coloration and character.


He had the good luck to age well, too. In 1988, at 62, he sang an all-Schumann program at Carnegie Hall, where people overflowed onto the stage to hear him. Donal Henahan, then the chief music critic of The New York Times, noted that Mr. Fischer-Dieskau’s voice had begun to harden in some difficult passages — but also that he was tall and lean and handsomer than ever, and had lost none of his commanding presence.


Mr. Fischer-Dieskau described in his memoir “Reverberations” (1989) how his affinity for lieder had been formed in childhood. “I was won over to poetry at an early age,” he wrote. “I have been in its thrall all my life because I was made to read it, because it gave me pleasure, and because I eventually came to understand what I was reading.”


He discerned, he said, that “music and poetry have a common domain, from which they draw inspiration and in which they operate: the landscape of the soul.”


Albert Dietrich Fischer was born in Berlin on May 28, 1925, the youngest of three sons born to Albert Fischer, a classical scholar and secondary school principal with relatively liberal ideas about education reform, and his young second wife, Theodora Klingelhoffer, a schoolteacher. (In 1934, Dr. Fischer added the hyphenated “Dieskau” to the family name; his mother had been a von Dieskau, descended from the Kammerherr von Dieskau, for whom J. S. Bach wrote the “Peasant Cantata.”)


Family members knew Dietrich, as he was called, as a shy, private child who nonetheless liked to entertain. He put on puppet shows in which he voiced all the parts, sometimes for an audience of one: his physically and mentally impaired brother, Martin, with whom he shared a room.


Before adolescence Dietrich was inducted into a Hitler Youth group where, he recalled years later, he was appalled by the officiousness as well as the brutality. His father died when he was 12. And he had just finished secondary school and one semester at the Berlin Conservatory when, in 1943, he was drafted into the Wehrmacht and assigned to care for army horses on the Russian front. He kept a diary there, calling it his “attempt at preserving an inner life in chaotic surroundings.”


“Poems by Morgenstern,” read one entry. “It is a good idea to learn them by heart, to have something to fall back on.”


“Lots of cold, lots of slush, and even more storms,” read another. “Every day horses die for lack of food.”