The songs are either for solo voice or an ensemble, or rarely a combination of solo songs mingled with choral pieces. The number of songs in a song cycle may be as brief as two songs or as long as 30 or more songs. The term "song cycle" did not enter lexicography until 1865, in Arrey von Dommer's edition of Koch’s Musikalisches Lexikon, but works definable in retrospect as song cycles existed long before then. One of the earliest examples may be the set of seven Cantigas de amigo by the 13th-century Galician jongleur Martin Codax.
A song cycle is similar to a song collection, and the two can be difficult to distinguish. Some type of coherence, however, is regarded as a necessary attribute of song cycles. It may derive from the text (a single poet; a story line; a central theme or topic such as love or nature; a unifying mood; poetic form or genre, as in a sonnet or ballad cycle) or from musical procedures (tonal schemes; recurring motifs, passages or entire songs; formal structures). These unifying features may appear singly or in combination. Because of these many variations, the song cycle "resists definition". The nature and quality of the coherence within a song cycle must therefore be examined "in individual cases".
Although most European countries began developing the art song genre by the beginning of the 19th century, the rise of Lieder in "Austria and Germany have outweighed all others in terms of influence." German-language song composition at the end of 18th century shifted from accessible, Strophic form, more traditional folk songs to 19th century settings of more sophisticated poetry for a more educated middle class, "who were gradually supplanting the aristocracy as the main patrons of the arts". Since these songs were relatively small-scale works, like the lyric poetry used for their musical settings, they were often published in collections, and consequently borrowed various poetic terms to mark their groupings: Reihe (series), Kranz (ring), Zyklus (cycle) or Kreis (circle). In the first few decades of the 1800s, the collections of poetry and the subsequent song settings took on more underlying coherence and dramatic plot, giving rise to the song cycle. This coherence allowed the song genre to be elevated to a "higher form", serious enough to be compared with symphonies and cycles of lyric piano pieces.
Two of the earliest examples of the German song cycle were composed in 1816: Beethoven's An die ferne Geliebte (Op. 98), and Die Temperamente beim Verluste der Geliebten (J. 200-3, \Op. 46) by Carl Maria von Weber.
The genre was firmly established by the cycles of Schubert: his Die schöne Müllerin (1823) and Winterreise (1827), settings of poems by Wilhelm Müller, are among his most greatly admired works. Schubert's Schwanengesang (1828), though collected posthumously, is also frequently performed as a cycle.