A circus is commonly a traveling company of performers that may include acrobats, clowns, trained animals, trapeze acts, hoopers, tightrope walkers, jugglers, unicyclists and other stunt-oriented artists. The word also describes the performance that they give, which is usually a series of acts that are choreographed to music. A circus is held in an oval or circular arena with tiered seating around its edge; in the case of traveling circuses this location is most often a large tent called the big top.
In Ancient Rome the circus was a building for the exhibition of horse and chariot races, equestrian shows, staged battles, displays featuring trained animals, jugglers, and acrobats. The circus of Rome is thought to have been influenced by the Greeks, with chariot racing and the exhibition of animals as traditional attractions. The Roman circus consisted of tiers of seats running parallel with the sides of the course, and forming a crescent around one of the ends. The lower seats were reserved for persons of rank; there were also various state boxes, eg. for the giver of the games and his friends. In Ancient Rome the circus was the only public spectacle at which men and women were not separated.
The influence of the American circus brought about a considerable change in the character of the modern circus. In arenas too large for speech to be easily audible, the traditional comic dialog of the clown assumed a less prominent place than formerly, while the vastly increased wealth of stage properties relegated to the background the old-fashioned equestrian feats, which were replaced by more ambitious acrobatic performances, and by exhibitions of skill, strength and daring, requiring the employment of immense numbers of performers and often of complicated and expensive machinery.
The modern concept of a circus as a circular arena surrounded by tiers of seats, for the exhibition of equestrian, acrobatic, and other performances seems to have existed since the late 18th century. The popularity of the circus in England may be traced to that held by Philip Astley in London, the first performance of his circus is said to have been held on January 9, 1768. One of Astley’s major contributions to the circus was bringing trick horse riding into a ring, though Astley referred to it as the Circle. Later, to suit equestrian acts moving from one circus to another, the diameter of the circus ring was set at 42 feet (13 m), which is the size ring needed for horses to circle comfortably at full gallop. Astley never called his performances a ‘circus’; that title was thought up by his rival John Hughes, who set up his Royal Circus a short distance from Astley’s ‘Amphitheatre of Equestrian Arts’ in Lambeth, London.