A tone poem, also called a symphonic poem, is an orchestral composition that evokes or illustrates some non-musical material, such as a landscape, poem, folk tale or other work of literature, a mood, an idea, or national spirit, and that usually consists of a single, extended movement. This contrasts with most classical music, which is absolute music — that is, it is not about anything in particular other than the music itself — and is usually divided into several movements if lengthy.
The term apparently was first used (in German) by the composer Carl Loewe in 1828, and composing in this genre became popular from about the 1840s until the 1920s. The tone poem represented a major innovation in orchestral music because it allowed composers to create their own musical structures instead of being confined by the then rigid structures (including melodic development and number of movements) that audiences expected for symphonies, concertos, and other orchestral works. At a time when it was widely thought that orchestral music has reached its limits of development with Beethoven's symphonies, tone poems reinvigorated such music and allowed it to develop into a much more encompassing art form and into an alternative to opera.