His work in this field deeply influenced his style of composition, which is, however, very much more severe in its apparent mathematical organisation than much of what Kodály wrote.

He was out of sympathy with the government that replaced the immediate post-1918 Republic in Hungary, where he was less appreciated than abroad.

In 1940 he emigrated to the United States where he died of leukaemia in 1945.

The two Violin Concertos are important additions to the solo violin repertoire.

The Viola Concerto and the Third Piano Concerto, left in various stages of incompleteness when Bartok died, are moving works, while the two earlier Piano Concertos have much to offer.

Other important orchestral works that form not infrequent parts of concert programmes are the "Divertimento for strings" and his impressionistic "Music for Strings, Percussion and Celesta".

The energetic "Romanian Dances" appear in various versions, including one for solo violin and string orchestra, arranged from an original piano composition.

Bartok's six string quartets are a significant and important part of repertoire, extending the musical and technical range of the form.

The 44 Duos for two violins are primarily educational compositions, but make attractive concert pieces in various groupings suggested by the composer.

A work of greater importance is the spectacular "Sonata for two pianos and percussion", later rescored by the composer for 2 pianos and orchestra.

The original version makes use of three kettle-drums, a xylophone, two side-drums, cymbals, suspended cymbal, bass drum, triangle and tam-tam, and two pianos.

It has an extended first movement, a second nocturnal one and a tautly rhythmic third.

Written in 1937, the sonata experiments effectively with the varied percussive sonorities of pianos and percussion instruments.

Mikrokosmos consists of six volumes of graded piano pieces intended for teaching, the last two volumes including more demanding pieces possible for concert use.

Folk melodies form the basis of 85 Pieces for Children, while the "Allegro barbaro" shows the composer in a more aggressive mood.