The larvae, also known as lemures, were, according to Etruscan tradition (later inherited by the Romans), ghosts of the dead who, having not yet found their rest, wandered the world during the night to atone for their crimes.
It is said that the larvae followed men in order to induce them to commit evil deeds or simply to frighten them.
To appease the larvae, the Romans resorted to various means: beating drums, striking a bronze vessel (because the larvae were said to fear this sound), imploring the protection of ancestral spirits, or holding festivals (the Lemuria festivals).