Born on Lesbos in the second half of the 7th cent. bce, she was hailed in antiquity as ‘the tenth Muse’ (Anth. Pal. 9. 506), and her poetry was collected into eight or nine books (arranged mainly by metre) by Alexandrian editors. Only two whole poems (one completed by a recent discovery) and some substantial fragments survive, culled from quotations in other writers or from papyrus finds.

Most of her poems were for solo performance, and many refer to love between women or girls. Other subjects include hymns to deities and apparently personal concerns such as her brother's safety (fr. 5). Wedding songs, and snatches from a lament for Adonis (fr. 140) are clearly for several singers. Fr. 44, describing the marriage of Hector and Andromache, is unusual in its narrative length and proximity to epic.

Little about her life is certain: biographies (POxy.1800, Suda, ‘Sappho’) are late and sometimes contradictory. She may have had some involvement in the aristocratic power struggles of Lesbos (fr. 71), leading to a period of exile in Sicily (Marm. Par.36). She was probably married, though only a brother and (probably) a daughter, Cleis, figure in the poems. The story of her suicide for love of Phaon is almost certainly fictional.

Her sexual inclinations have occasioned much speculation from antiquity to the present. From Attic comedy onwards she was credited with an implausible selection of male lovers. She is described as a lover of women only in post-Classical times, and in later European tradition was often regarded as heterosexual. See homosexuality.

Her own poetry remains the major source for the controversial question of how she related to the companions (fr. 160) who formed her audience. An important parallel is Alcman's partheneia (maiden-songs) written for girls' choruses, in which the singers praise each other in erotic terms. Sappho often calls her companions parthenoi (girls). This, and the frequent references to partings and absence in her poems, suggest that most of her circle shared their lives for only a limited period before marriage. Homoeroticism was probably institutionalized at this stage of life, as it was elsewhere for young men. The group's preoccupations—love, beauty, poetry—are indicated by the divinities most often invoked in Sappho: Aphrodite, the Graces (see charites), and the Muses.

But despite the likely socializing and religious function of her group, Sappho herself emerges from the poems as far from the chaste headmistress figure constructed by 19th- and early 20th-cent. German philology. In fr. 1, the poet names herself in a prayer enlisting Aphrodite's help in winning the love of an unresponsive girl. In fr. 16 the singer links her own love for the absent Anactoria with that of Helen for Paris, and fr. 31 famously charts the singer's despair as she watches a beloved girl sitting next to a man. Sappho's love poetry differs from that of male writers in the almost complete absence of a sharp distinction between lover and beloved.

Poems such as these reveal an accomplished poet who can achieve effects of great subtlety beneath an apparently simple surface; other, less complex poems (frs. 102, 114) seem influenced by folk-song. Like her contemporary Alcaeus (1) she writes in a literary Aeolic dialect (see greek language, §4). Her work was admired in antiquity for its euphony (Dion. Hal.Comp. 23) and she was credited with musical invention; the Sapphic stanza was used by later poets such as Horace. Notable imitations include Catullus (1) 51, 61, and 62, while Ovid's imaginary epistle from Sappho to Phaon (Her. 15) was the progenitor of many subsequent fictions about her.