Sextus Propertius was a Latin elegiac poet of the Augustan age. He was born around 50–45 BC in Assisium (now Assisi) and died shortly after 15 BC.

Propertius's surviving work comprises four books of Elegies (Elegiae). He was a friend of the poets Gallus and Virgil and, with them, had as his patron Maecenas and, through Maecenas, the emperor Augustus. Although Propertius was not as renowned in his own time as other Latin elegists, he is today regarded by scholars as a major poet.

Very little information exists about Propertius outside of his own writing. His praenomen "Sextus" is mentioned by Aelius Donatus, a few manuscripts list him as "Sextus Propertius", but the rest of his name is unknown. From numerous references in his poetry it is clear he was born and raised in Umbria, of a well-to-do family at or near Asisium (Assisi). His birthplace is generally regarded as modern Assisi, where tourists can view the excavated remains of a house thought to have belonged at least to the poet's family, if not to the poet himself.

During Propertius's childhood, his father died and the family lost land as part of a confiscation, probably the same one which reduced Virgil's estates when Octavian allotted lands to his veterans in 41 BC. Along with cryptic references in Ovid that imply that he was younger than his contemporary Tibullus, this suggests a birthdate after 55 BC.

After his father's death, Propertius's mother set him on course for a public career, indicating his family still had some wealth, while the abundance of obscure mythology present in his poetry indicates he received a good education. Frequent mention of friends like Tullus, the nephew of Lucius Volcatius Tullus, consul in 33 BC, plus the fact that he lived on Rome's Esquiline Hill indicate he moved among the children of the rich and politically connected during the early part of the 20s BC.

Propertius published a first book of love elegies around 30 BC, with the character 'Cynthia' as the main theme; the book's complete devotion gave it the natural title Cynthia Monobiblos. The Monobiblos must have attracted the attention of Maecenas, a patron of the arts who took Propertius into his circle of court poets. A second, larger book of elegies was published perhaps a year later, one that includes poems addressed directly to his patron and (as expected) praises for Augustus. The 19th century classics scholar Karl Lachmann argued, based on the unusually large number of poems in this book and Propertius's mention of tres libelli, that the single Book II actually comprises two separate books of poetry conflated in the manuscript tradition, an idea supported by the state of the manuscript tradition of "Book II." An editor of Propertius, Paul Fedeli, accepts this hypothesis, as does G.P. Goold, editor of the Loeb edition.

The publication of a third book came sometime after 23 BC. Its content shows the poet beginning to move beyond simple love themes, as some poems (e.g. III.5) use Amor merely as a starting point for other topics. Book IV, published sometime after 16 BC, displays more of the poet's ambitious agenda, and includes several aetiological poems explaining the origin of various Roman rites and landmarks.

Book IV, the last Propertius wrote, has only half the number of poems as Book I. Given the change in direction apparent in his poetry, scholars assume only his death a short time after publication prevented him from further exploration; the collection may in fact have been published posthumously. An elegy of Ovid dated to 2 BC makes it clear that Propertius was dead by this time.