The Amadeus Quartet was a world famous string quartet founded in 1947 and disbanded in 1987, remarkable for having retained its founding members throughout its long history.

Because of their Jewish origin, the violinists Norbert Brainin (12 March 1923 – 10 April 2005), Siegmund Nissel (3 January 1922 – 21 May 2008) and the viola player Peter Schidlof (9 July 1922 – 16 August 1987) (later violist) were driven out of Vienna after Hitler's Anschluss of 1938. Brainin and Schidlof met in a British internment camp on the Isle of Man; many Jewish refugees had the misfortune of being confined by the British as "enemy aliens" upon seeking refuge in the UK. Brainin was released after a few months, but Schidlof remained in the camp, where he met Nissel. Finally Schidlof and Nissel were released, and the three of them were able to study with violin teacher Max Rostal, who taught them free of charge. It was through Rostal that they met cellist Martin Lovett, and in 1947 they formed the Brainin Quartet, which was renamed the Amadeus Quartet in 1948.