Catullus' family owned a villa at Sirmio on Lake Garda. His father entertained Caesar, then governor of Gaul. At some point, the poet parodied Caesar and an associate (Mamurra), but later apologized and was forgiven.
Catullus' friends included the poets C. Licinius Macer Calvus, Marcus Furius Bibaculus, and C. Helvius Cinna, the orator Quintus Hortensius (a rival of Cicero in the law courts) and the biographer Cornelius Nepos, to whom Catullus' book of poems is dedicated.
In 61 BC Catullus went to Rome and fell in love with the "Lesbia" of his poems, generally believed to be Clodia Metelli, sister of the infamous Publius Clodius Pulcher. This sophisticated woman, 10 years older than Catullus, was a member of the aristocratic Claudian family. Their brief affair ended when Clodia spurned him for Marcus Caelius Rufus, a member of Catullus' social circle and an associate of Cicero.
In 57 BC he accompanied his friend Memmius to Bithynia, where Memmius served as propraetor. Catullus served on the staff of the governor of Bithynia, his only political office. While in the East, Catullus traveled to the Troad to perform rites at his brother's tomb, an event recorded in a moving poem.
After his year in Bithynia, Catullus returned to Italy, probably settling in Rome and spending the last few years of his life there. Although his poems contain complaints about poverty, he owned a villa near Tibur (modern Tivoli).
It is uncertain when Catullus died. Some ancient sources claim he died from exhaustion at the age of thirty. St. Jerome gives his birth year as 87 BC and wrote that the poet lived 30 years, but some of the poems refer to events in 55 BC. Since no poem can be dated later than 54 BC, scholars traditionally accept the dates 84 BC – 54 BC.
His poems were widely appreciated by other poets, but Cicero despised them for their supposed amorality. Catullus was never considered one of the canonical school authors. Nevertheless, he greatly influenced poets such as Ovid, Horace, and Virgil. After his rediscovery in the late Middle Ages, Catullus again found admirers. His explicit writing style has shocked many readers, both ancient and modern.
There is no scholarly consensus on whether or not Catullus himself arranged the order of the poems. The longer poems differ from the polymetra and the epigrams not only in length but also in their subjects: There are seven hymns and one mini-epic, or epillion, the most highly-prized form for the "new poets".
The polymetra and the epigrams can be divided into four major thematic groups (ignoring a rather large number of poems eluding such categorization):
All these poems describe the Epicurean lifestyle of Catullus and his friends, who, despite Catullus' temporary political post in Bithynia, lived their lives withdrawn from politics. They were interested mainly in poetry and love. Above all other qualities, Catullus seems to have sought venustas, or charm, in his acquaintances, a theme which he explores in a number of his poems. The ancient Roman concept of virtus (i.e. of virtue that had to be proved by a political or military career), which Cicero suggested as the solution to the societal problems of the late Republic, meant little to them.
But it is not the traditional notions Catullus rejects, merely their monopolized application to the vita activa of politics and war. Indeed, he tries to reinvent these notions from a personal point of view and to introduce them into human relationships. For example, he applies the word fides, which traditionally meant faithfulness towards one's political allies, to his relationship with Lesbia and reinterprets it as unconditional faithfulness in love. So, despite seeming frivolity of his lifestyle, Catullus measured himself and his friends by quite ambitious standards.
Catullus was also an admirer of Sappho, a female poet of the 7th century BC, and is the source for much of what we know or infer about her. Catullus 51 follows Sappho 31 so closely, that some believe the later poem to be, in part, a direct translation of the earlier poem, and 61 and 62 are certainly inspired by and perhaps translated directly from lost works of Sappho. Both of the latter are epithalamia, a form of laudatory or erotic wedding-poetry that Sappho had been famous for but that had gone out of fashion in the intervening centuries. Catullus sometimes used a meter that Sappho developed, called the Sapphic strophe. In fact, Catullus may have brought about a substantial revival of that form in Rome.
Many of the literary techniques he used are still common today, including hyperbaton: ‘’plenus saculus est aranearum’’ (Catullus 13), which translates as ‘[my] purse is all full – of cobwebs.’ He also uses anaphora e.g. ‘’Salve, nec minimo puella naso nec bello pede nec…’’(Catullus 43) (‘hello, girl with a not so small nose and a not so pretty foot and...’) as well as tricolon and alliteration. He is also very fond of diminutives such as in Catullus 50: ‘’Hestero, Licini, die otiose/multum lusimus in meis tabellis’’ – ‘Yesterday, Licinius, was a day of leisure/ playing many games in my little notebooks’.
Catulli Carmina is a cantata by Carl Orff to the texts of Catullus.
The new musical TULLY (In No Particular Order), which appeared in the 2007 New York Musical Theatre Festival, loosely adapts the poems of Catullus while retaining the non-linear structure of the published edition, exploring his relationships with both Clodia and Juventius, renamed Julie, and the timeless nature of memory and love.
Archiblad MacLeish wrote a poem entitled "You Also, Gaius Valerius Catullus," where he addresses the poet.
Catullus is discussed in John Fowles novel 'The French Lieutenant's Woman' (1969) as being one of the fore-most poets on love, sexuality and desire.