While Sibelius was composing his sixth symphony, he also began thinking about writing another orchestral piece, which would eventually become his last symphony, Symphony No. 7 in C Major, Op. 105 (the original form of one of the slow themes of the work actually appears in the sketch of his fifth symphony). Sibelius did not complete the symphony until the year 1924. It premiered in Stockholm, Sweden on March 24 of that year, approximately one year after the first performance of his sixth symphony. The composer himself conducted the Stockholm Concert Society Orchestra (now Royal Stockholm Philharmonic Orchestra).
The most notable feature of Sibelius’ Symphony No. 7 is that it has only one movement. Revealed in his letter to an unknown recipient written in 1918, Sibelius at first planed the piece to have three movements. His intention was to follow the success of his third and fifth symphonies, which he constructed with just three movements in place of the four-movement format commonly found in the traditional symphonies. During the long process of maturing his musical ideas to develop his Symphony No. 7, however, Sibelius decided to bring together all of the materials he had written into a single movement, an entirely new idea for him in composing a symphony. The end result is a composition that never loses intensity until its very last note.