For centuries Boy-Bishops were elected on St. Nicholas [Patron of Children] Day (6 Dec). He would reign til the Slaughter of the Innocents (28 Dec). This was most respected in England, until Henry VIII Tudor. Queen Mary brought it back. Elizabeth got rid of it for good.
About the time of the Circumcision (1 January) there was celebrated the Feast of Fools. Another day of merry making, that, the overly priggish and pious disapproved. It is centuries since it has been broadly celebrated, and the possible abuses have been exaggerated for polemical or prohibitory effect; the former to beat on catholicism by opponents of catholicism, and the latter to beat on catholics by establishment (lay or clerical) figures, whom, are jealous for their dignity.
Festum Asinorum, Feast of Asses, began with the dramatisation of a 6th century sermon, wherein the Prophets proclaim the Divinity of Jesus. Then Mass was celebrated. The part most beloved of the audience was Balaam and his Ass (before the Victorians, this referred to the animal without embarrassment). It became a separate play, the animal was a wooden prop. Extant western scripts go back to 1100. The Process of the Prophets became a celebration of the Ass.
Theophylact Lekapenos was Patriarch in Constantinople (933-56). He is credited with its introduction as a festival by the the monk George Cedranus who chronicled a history of the world (to 1057). The greek east and the latin west were not separated then. The celebration came to France. Liturgical drama was enjoyed. The hobby horse ass could become a parade. Liturgical drama were to include the Miracle and the Mystery Plays, and they in their last twilight in England were caught by Shakespeare. Now we have only the Children's Mass on Christmas Eve. Germans still have a Palm Esel (Palm Sunday Ass) they roll into church.
On the 14th of January, in the carnival season before Lent, and after the celebrations of Christmas, the flight from Herod to Egypt was celebrated with a nod to the noble Ass. Merry making has been frowned upon by the modern world. The protestant 'reformers' disliked such amusements, aggrandising monarchs and modern catholic churchmen likewise.
We were more free in ages past. Authority was tempered by a social contract to prevent tyrannical behavior by the mighty. Jesters had their duties. The power of the king, and the bishop were tempered by the people. A social revolution was constrained festively. Oppressive and contemptible jerks in high office were kept in check.
Now, April Fools is a prankish day of minor mischief, that also some how, is associated with beginning in France. There are times when this can fall on Easter Monday. Easter Monday is a day of great joy. Jesus has defeated death. The Devil hates to be mocked, he is quite defeated on Easter, and Easter Monday. Laughing at the proud Devil who fancies himself as the master of the world is something we need to do. Electing a boy bishop is a practice we can resurrect.
Orientis partibus adventavit asinus ...