The first sonata was published already the year after it had been written and was given its première by Karl Wagner and Reger at the Museumssaal of the Palais Portia in Munich on 18 April 1902. The much feared critic Rudolf Louis regarded the slow movement as "one of the best pieces Reger has ever written".

Reger kept following the four movement pattern from Brahms's F minor sonata: opening sonata movement, scherzo with a sostenuto trio, expressive slow movement and final sonata movement. Within this rather traditional structure, however, Reger developed his own individual musical language. His treatment of the thematic material, the invention of unknown and original harmonic progressions, his expressive dynamics as well as an intricate way of phrasing, make him very distinctly a twentieth-century composer.

After he had completed writing the sonatas Reger tested them in a private concert. Lindner continued: "...Kürmeyer, who had studied his part thoroughly, managed this rather difficult task in the best possible way-and to the full satisfaction of the master. In the end even the very critical father seemed highly content with each movement..." They repeated the first and last movement of the first sonata several times because of their complex comprehensibility and hidden beauties. Lindner wrote:"...most of all we were delighted by the catchy and gracious second movement with its wonderfully sweet sostenuto episode, which appearing three times is reminiscent of the familiar folk-song 'Ach wie ist's möglich dann?' ('Oh how is it possible?'), and by the unworldly and dreamy Larghetto with its più mosso assai middle section in B flat minor, which depicts a furious but quickly dissolving awakening. The creator of this work, which is full of longing, sang himself into everyone's heart. The last movement (6/4, Prestissimo) again breathes a healthy, almost exuberant sense of humor...".

Writer: Jürgen Schaarwächter
Translated by: Jakob Fichert