Karl Aagaard Østvig (sometimes Germanized to Oestvig) (17 May 1889 - 21 July 1968) was a Norwegian operatic tenor, opera director, and voice teacher. The Norwegian Music History Archive states that he is the greatest dramatic tenor in Norwegian history, and that he was particularly admired for his portrayals in operas by Giacomo Puccini, Richard Strauss and above all Richard Wagner. His voice was described by soprano Lotte Lehmann as "a dazzling meteor". Although he toured internationally in concerts, operas, and recitals, his singing career was mainly centered in Austria and Germany from his debut in 1914 up until his retirement from the stage in 1933. From 1932 on he lived in Oslo where he was primarily active as an opera director and singing teacher. He made only a few recordings during his career, all for Polydor Records.