Piano Sonata no. 14 Quasi una fantasia is more popularly known by the title of the Moonlight Sonata. This name is derived from the comments of music critic Ludwig Rellstab following Beethoven's death. Rellstab made the observation that the piece's first movement sounded like the reflection of moonlight upon Lake Lucerne. The Moonlight Sonata was written in 1801 and dedicated to Beethoven's pupil, Giulietta Guicciardi, in 1802. It is a popular sonata for many reasons, but a primary reason is its accessibility to beginners much like Beethoven's Für Elise.
In terms of form, the Moonlight Sonata does not follow the typical structure of a Classical sonata, fast-slow-fast. Instead, Beethoven uses a gave the piece a trajectory from slow to fast, reserving the highest energy movement for the last.
The first movement is written in C# minor and approximately a sonata form. It is textured with a clear accompaniment underlying ostinato eighth notes, which places us firmly in the Classical era. Although, the dynamic is predominantly written at piano or pianissimo, the use of sforzando and other strong dynamics gives us an idea that this may be a later work. The second movement moves to the parallel major key, which is a characteristic that narrows the options down to Mid- or Late-Classical era. The third and final movement then goes back to the original key of C# minor and gives us our best insight into placing this piece in the Late-Classical period.
The final movement is the most foreshadowing (musically speaking) to the Romantic period. It has an unbridled display of emotion that is evoked through the use of energetic tempi and sudden, extreme changes in dynamic.
Written in 1801, this piece is chronologically in the earliest parts of the Late-Classical. However, the third movement gives us a major foreshadowing of Romanticism with its dramatic energy. Although this piece demonstrates a massive amount of emotion, it still remains a better fit with the Late-Classical period. The use of clear, predominant melodies and the fact that it is written for piano are major indicators of that. The rhythmic vocabulary is also astonishingly simple compared to music of the Romantic period. The common title of this piece is misleading because of the fact that it was not nicknamed until the Romantic period. Beethoven stuck to the Classical system of numbering works rather than giving them more thematic titles.
The structure of this sonata is atypical, as mentioned before, because Beethoven was experimenting with placing the most important movement last. This clearly failed due to the fact that, likely, many people have heard the first movement and not the second or, much less, the third. Also, the piece's nickname is even derived from the mood that is evoked in the first movement.
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