The Classical period saw a revolution of Greek sculpture, sometimes associated by historians with the popular culture surrounding the introduction of democracy and the end of the aristocratic culture associated with the "kouroi". The Classical period saw changes in the style and function of sculpture, along with a dramatic increase in the technical skill of Greek sculptors in depicting realistic human forms. Poses also became more naturalistic, notably during the beginning of the period. This is embodied in works such as the "Kritios Boy" (480 BC), sculpted with the earliest known use of "contrapposto" ('counterpose'), and the "Charioteer of Delphi" (474 BC), which demonstrates a transition to more naturalistic sculpture. From about 500 BC, Greek statues began increasingly to depict real people, as opposed to vague interpretations of myth or entirely fictional votive statues, although the style in which they were represented had not yet developed into a realistic form of portraiture. The statues of Harmodius and Aristogeiton, set up in Athens mark the overthrow of the aristocratic tyranny, and have been said to be the first public monuments to show actual individuals.