Chopin Nocturne - Harmonic Analysis of Bars 1-16

For the purpose of this analysis, I will abbreviate Left Hand to LH and Right Hand to RH.

This piece begins in C minor, with the LH chords playing chords I, V, I, VI (for the first bar). This accompanies the RH which plays V and VI with the LH chords (G, A). In the second bar, the LH moves down to the subdominant note, B, and the RH moves down with it, back to the G (V). Then the LH has a chord V7, before moving back to the chord I that it had before, and an inverted chord I after that. On top of that, the RH plays a short motif that is based on D, the supertonic. This provides tension here, because it goes against the generally I and V pattern in the LH. Then in bar 3, the RH returns to the tonic, which would sound like a resolve, except the LH has chord VI, and so puts us into briefly into Am. Then the LH has chord IV and a chord consisting of F, C, and D. This goes with the RH playing a D, which is a suspension, because the RH then resolves down to C, and with the LH chord V that soon accompanies it, (along with the G that we then get in the RH), we are now back to the tonic in bar 4. Beat two of the bar is a chord of F, G and B, which is an inverted V7 chord in GM, and wants to resolve to CM, which we then get in beat 3 of the bar. In the right hand we get a neighbouring note with the A. This is followed by a chord V (E and G), creating an imperfect cadence for the end of the phrase. In bar 5 we have a 2nd inversion diminished Em chord, which is the mediant. This goes to a root position V7 chord in FM, the subdominant. If we look ahead at the next few chords in the LH, which are octaves of Bb, B, and C respectively, it becomes clear that we are moving chromatically up the keys in this section of the piece. Then in bar 7, the LH moves up a tone to D, providing a change to the chromaticism and reaffirming our interest. It is clear here that we are in D, because the RH plays a motif based on D, and then in the LH we get Ds and then F and A- a Dm chord. However the F# in the RH creates a dissonance which is only resolved when it goes to a G in the 3rd beat of the bar and we get a chord of GM. In bar 9, the LH moves down to Gb and then F, another example of chromaticism. In the next bar the RH flurries around the submediant and the subdominant, and under that the LH chords are VI, VI,  IV (minor- a borrowed chord), and back to I. In the next bar (bar 11), there are passing tones in the RH part between beats 1 and 2 (A and B), and there is an escape tone in beat 4 (C). In the LH we get another semi-chromatic pattern in the chords- leading tone, tonic, supertonic, mediant, with two V7s interspersed between them for interest. Then the LH begins to go back down, through the subdominant and mediant, then down to the tonic and the leading tone in the next bar. In the RH, beat 2 is a retardation, because it is a B, which wants to and then does resolve up to C (I). In the next bar the LH has a V7 chord which then resolves to Ic. In the next bar the LH has octave F's, and then the chord of F. Then it moves up to A, and then the chord of F again, which provides interest, but without changing the key, so that it remains in the subdominant, to remain there for the next bar.