One of the most obvious and official celebrations which takes place in Julius Caesar by William Shakespeare is the Feast of Lupercal.
This feast began in ancient times as both a religious celebration and a fertility rite. It was a Roman holiday celebrated in the place where the founding brothers, Romulus and Remus, were once nursed by a female wolf to survive. The celebration was held in mid-February, and the activities of the original festival included the following:
the priests slaughter goats, and then, after two youths of noble birth have been brought to them, some of them touch their foreheads with a bloody knife, and others wipe the stain off at once with wool dipped in milk. The youths must laugh after their foreheads are wiped. After this they cut the goats' skins into strips and run about, with nothing on but a girdle, striking all who meet them with the thongs, and young married women do not try to avoid their blows, fancying that they promote conception and easy child-birth.
Obviously there is an element of fertility ritual which is part of the entire celebration.
By the time Shakespeare was writing, the Feast of Lupercal, known as the Lupercalia, was no longer celebrated as the ancients did. The Pope finally stopped this celebration (mostly due to the naked young men running through the streets), though elements of it lived on in a festival celebration known as Februaria which was more about ritual cleansing and washing to celebrate spring.
In Julius Caesar, Shakespeare clearly refers to the ancient traditions of the Feast of Lupercal. Julius Caesar tells Calphurnia to make certain she stands directly in Antonio's way as he runs through the streets during the celebration. When Antony questions the remark, Julius Caesar explains:
Forget not, in your speed, Antonio,
To touch Calphurnia; for our elders say,
The barren, touched in this holy chase,
Shake off their sterile curse.
Though we can presume that Antonio and the others are not running through the streets naked, we can presume that they will be observing the practice of plying bloody strips of goatskin and that Caesar, at least, believes there is some validity to the notion of fertility being conferred on the married women who are touched with those strips.
We also know that in the play people do not have to work during the celebrations and that statues of Julius Caesar are decorated with flowers and many other things. The entire city knew about and participated in the festival because they understand when Marc Antony alludes to it in his famous speech.
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