In 1963-1964 he sang at the Glyndebourne Festival the role of Flamand in Capriccio by R. Strauss, in 1962-1963 at the Bayreuth Festival the role of Froh in Rheingold.
During his distinguished career he also performed as a concert and oratorio singer.
During World War II, he became a soldier and was in English captivity until end of the war.
Since 1973 Horst Wilhelm taught at the Musikhochschule of Lübeck.
Horst Wilhelm made his debut 1951 at the Städtischen Oper Berlin, where he was engaged until 1956 as the first lyric tenor.