The Sonata in E for Violin and Piano composed in the summer of 1935 opened a series, completed in 1955, of a total of 26 sonatas for winds, strings, piano, organ and harp, 17 of which Hindemith had already composed by the time of his departure for the United States in February 1940. He explained some of his motivations for composing these works to his publisher Willy Strecker in November 1939: «You will be surprised that I am writing sonatas for all the wind instruments. I already wanted to write a whole series of these pieces. First of all, there's nothing decent for these instruments except for a few classical things; although not from the present business perspective, it is meritorious over the long term to enrich this literature. And secondly, since I myself have been so interested in playing wind instruments, I have great pleasure in these pieces. Finally, they are serving me as a technical exercise for the big punch with which the ‹Harmonie der Welt› [...] can hopefully be begun in the spring.»
The sonatas do indeed reflect the music-theoretical knowledge gained by Hindemith during his work on Unterweisung im Tonsatz. The three-voiced writing in which all the sonatas are composed are the expression of a conviction that a listener can perceive no more than three simultaneously sounding voices with any degree of differentiation. Moreover, the unequivocal harmonic arrangement of sounds is only possible starting with three voices. Other basic principles developed in Hindemith's music theory, such as the preference for steps of seconds in the melody are also integrated into the composition.
If the sonatas appear «standardised» in their writing technique in accordance with Hindemith's music theory, they nonetheless have their unmistakable profiles. Each of the sonatas is like a musical portrait of the instrument for which it is written. They also have individuality thanks to the variety of forms in which they are cast, especially shown in the unconventional final movements. The final movement of the three-movement Sonata for Flute and Piano is expanded by a March that appears as an independent fourth movement. At the end of the two-movement Sonata for Bassoon and Piano is a sequence of three sections which are thematically independent of each other, like character pieces. The four-movement Sonata for Clarinet and Piano ends with a cheeky «little rondo.»
The extensive production of sonatas reflects Hindemith's personal life situation during the 1930s. Since public concert performances were hardly possible for him any more, he resorted to making music at home with his wife, for which occasions the sonatas formed a welcome enrichment – with the exception of the harp, Hindemith could play all the instruments. For this reason, he asked Willy Strecker in December 1939: «If you could make a photo of the Trumpet Sonata and send me the manuscript, I would be grateful; the piece has become part of our daily music-making, which is why we don't want to be without it.»
Concrete biographical references can be noted in several of the sonatas. The First Sonata for Piano which, in Hindemith's own words, «was stimulated by the poem ‹Der Main› by Friedrich Hölderlin,» is the expression of his love for his homeland, from which he feared to be banished before the backdrop of the National Socialist animosities. The grief over the outbreak of World War II is articulated in the funeral march conceived as a chorale adaptation of ‹Alle Menschen müssen sterben› (All People Must Die) which concludes the Sonata for Trumpet and Piano.