Commedia dell ‘Arte, or Comedy of the artist, was a form of improvised theatre from Italy popular in the Middle Ages, and surprisingly to me, as someone who has studied comedy and improvisation extensively over the past few years, not well known by people today.
As a part of carnival festivities, Commedia Dell ‘Arte was an escape from the drudgery of the type of lives the poor and underclasses eeked out, and a break from the oppression of the ruling class. It was an opportunity for people to make fun of both themselves and the rich and the royal, to blow off steam, and not take life too seriously.
Actors who performed in Commedia Dell ‘Arte would choose one of a series of stock characters, with very specific masks and costumes, routines and mannerisms, that were well known to the people of the day, as was the game, or unusual funny thing about them, which could be repeated over and over. Some of the characteristics included the quick-bodied dumb man, the dirty old man, the bad tempered hunch back, the dandy, and the vocal know it all who actually knows nothing, and are character traits which have survived all the way to today, and still form the basis behind much of the comedy produced in modern times, and everything in-between including harlequins, clowns, and vaudeville.
These characters were much like modern sitcoms characters, where people who tune in know certain behavioral attributes each character will have, which new story lines are filtered through each week, such as Sheldon from the Big Bang Theory will always respond to people in a social retarded yet ridiculously intelligent way, or Joey from friends who is always eating and saying dumb things. And I believe the sitcom Arrested Development was specifically created and designed to include one of each of the archetypal comedic characters that are popular today and seem to have developed from these original archetypes from the middle ages.
Much like the modern sitcom Commedia Dell ‘Arte would follow familiar patterns often through stock plots, and lazzies, or rehearsed comedic routines, only with improvised dialogue to allow them to remain fresh, and unique to each individual performance.
Performers would play one character often for their entire lives, so it was seemingly a craft that could always be improved upon yet never mastered. The performers were not well respected in their time, but whoever created these stock characters surely most be among the most important artists in comedy history.