Catullus was a poet from the time of the establishment of the Roman Empire and Julius Caesar. His poetry was well liked and he was well-respected and considered one of the"new men" in Rome. He chose to write about personal issues rather than battles which was quite revolutionary for its time. For these personal issues, he chose to write in easy to understand "street" language to get his message across. He did however maintain a poetic form that was not of his own invention but was a reflection of Greek and Alexandrian poetry,
[he used] the meters of late Greek literature of the Alexandrian school
thus earning himself the title "Learned" Catullus.
The poetry of Catullus was divided, probably after his death, into collections and his erotic love poetry is thought to be some of the earliest recorded works of this nature - the subject being mostly taboo in the written form.
Catullus also wrote scathing poetry about well-known men, notably Caesar, using shocking and profane language without caring about any repercussions.
The acclaimed Catullus wrote in a form easily recognizable today while inventing theme, styles and modes still apparent today in contemporary poetry (eNotes).
Modern poets applaud the language as used by Catullus, as spoken by ordinary people. The ability to write poetry without falling into the trap of rhetoric or "'poetic' dialect was a remarkable achievement."