One of Respighi's two piano concertos, composed in 1925. This piece was written during Respighi's tenure as a professor at the Santa Cecilia Conservatory in Rome, a period when he was actively composing and successively releasing major works such as Pines of Rome (1924), Fountains of Rome (1928), Church Windows (1926), and Botticelli Triptych (1926). At 46 years old, he was at the height of his creative powers, making this concerto a work from Respighi's peak period.

Since encountering Luigi Torchi, a master of early music research, during his studies at the Bologna Conservatory, Respighi developed an interest in ancient music. Within the Neoclassical movement that emerged from the late 19th to early 20th centuries, many composers, including Italians like Casella, Pizzetti, and Malipiero, as well as members of Les Six and Stravinsky, began to show interest in early music. However, Respighi's approach to early music was distinct from all of them. Respighi not only unearthed, arranged, and introduced ancient pieces that had been buried in history, but he also absorbed medieval and Renaissance musical forms and compositional techniques, fusing them within the frameworks of Romantic and Impressionistic music to establish his own new musical style. As one such endeavor, Respighi's Concerto in the Mixolydian Mode explored the possibilities of new music based on church modes, rather than the tonal music prevalent until then.

The "Mixolydian mode" in the title is one of the church modes used in the Middle Ages. It is structured as a major scale with the seventh degree, the leading tone, lowered by a semitone. While it may lack some tension compared to tonal harmony due to the absence of a leading tone, it is characterized by a pastoral and bright atmosphere and is frequently used not only in classical music but also in jazz and pop.

1st Movement: Moderato

The concerto opens with a brilliant and elegant piano solo, characteristic of Respighi. Both the melody and harmony of this piano part are beautiful. The incorporation of new musical techniques extends not only to the church mode, which is part of the title, but also to the musical structure. Unlike the thematic development seen in music from the Classical period onward, the piece is structured in a form unbound by strict conventions, where themes emerge and disappear in various guises. This demonstrates Respighi's commitment to a different musical approach than his previous works.

2nd Movement: Lento-Andante con moto

The movement begins with a theme of grand scale, and the piano progresses the music by accompanying the melody played by the cello. Similar to the first movement, it is written in a relatively free style, unconstrained by traditional forms. The relationship between the piano and orchestra also differs from the typical style of conventional piano concertos, giving the impression of the orchestra providing a subdued accompaniment to the piano's solo. This reflects Respighi's challenge to break away from traditional musical styles and construct his own unique music, at a time in the early 20th century when the classical music world as a whole was seeking new sounds and moving towards avant-garde music such as atonality.

3rd Movement: Passacaglia-Allegro energico

Connected attacca to the second movement, it opens with a piano fanfare. The orchestra, which had maintained a somewhat restrained expression in the first and second movements, is suddenly unleashed in the third movement, bursting into vibrant life alongside the piano. Concertante passages for piano and orchestra also appear, and the themes and their development are clear and approachable. In the finale, brilliant and virtuosic piano passages combine with a splendid and magnificent orchestral sound, bringing the work to a grand close. Here, Respighi's masterful orchestration, having reached his mature period, truly shines.