The handwritten score of this piece bears the inscription "Sonata No. 4," indicating it is not Brahms's first sonata. Although it became Op. 1 primarily due to publishing arrangements, it was actually composed after Op. 3, the sonata, and the Scherzo of Op. 4.

The first and second movements were composed in April 1852, and the third and fourth movements in the spring of 1853, both in Hamburg.

This sonata clearly shows the influence of Beethoven's Piano Sonatas "Waldstein" and "Hammerklavier". However, it is also not unrelated to the programmatic tendencies popular at the time. Characteristics that would later define Brahms's piano music, such as dynamic movement and the utilization of a wide range, are also discernible. It is a major work infused with the overflowing passion of the young Brahms, and Brahms himself seems to have been confident in this sonata.

The entire work is unified by the progressive development of the first movement's first theme.

First Movement

Allegro, C major, 4/4 time. Sonata form. The opening first theme became a topic of discussion due to its striking resemblance to the opening theme of Beethoven's "Hammerklavier".

Second Movement

Andante, C minor, 2/4 time. Takes the form of a free set of variations. It is inscribed "Nach einem altdeutschen Minnelied" (After an old German Minnelied), and in the score, the lyrics are appended to the 12-bar melody of the theme. The 49th piece of Brahms's later arranged "Deutsche Volkslieder" (German Folksongs), consisting of 49 songs, also features these lyrics. The gist of the lyrics is as follows:

• Solo: The moon rises softly
• Chorus: Little blue, blue flower (referring to the moon)
• Solo: Ascending to heaven through silvery clouds
• Chorus: Little blue, blue flower
• Roses in the valley, maidens in the hall
• Oh, most beautiful rose in the world

This poem indicates the character of the entire movement and its musical expression.

The movement features three variations following the theme and proceeds without a break into the next movement.

Third Movement

Allegro molto e con fuoco, E minor, 6/8 time. Scherzo, ternary form. This movement also proceeds without a break into the next movement.

Fourth Movement

Allegro con fuoco, C major, 9/8 time. Rondo form, taking the shape of A–B–A–C–A–Coda. It is said that Brahms was inspired to write this movement by a German translation of the Scottish folk poet's poem "My Heart's in the Highlands".