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Circus Maximus -

Circus Maximus was ancient Rome's enormous chariot-racing stadium and mass entertainment complex. It held up to 250,000 spectators. The Latin word circus means "circle" or "ring."

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Philip Astley (1742–1814) -

Englishman Astley is considered to be the "father of the modern circus." An accomplished horseman, Astley founded a riding school in London where he performed trick-riding displays in a circle, hence the description "circus." 

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Astley's Amphitheatre - The success of these circus shows prompted the opening in 1773 of Astley's Amphitheatre. Astley hired acrobats, tightrope walkers, jugglers, and a clown to keep audiences amused between his equestrian antics—an integrated entertainment experience regarded as a forerunner of the modern circus show.

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Joseph Grimaldi (1778–1837) - The English actor, comedian, and dancer is generally regarded as the first mainstream clown to perform publicly in front of an audience.

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Grimaldi as "Joey" the Clown - The London comic won fame with his role as a Harlequin clown, delighting crowds in British pantomimes at a number of city venues including the Sadler's Wells and Covent Garden theaters.

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The Royal Circus -

The Royal Circus and Equestrian Philharmonic Academy opened in London in 1782, one of several circuses across the capital providing equestrian and theatrical entertainment.

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John Bill Ricketts (1769–1800) - Scotsman and equestrian Ricketts is credited with bringing the first modern circus to the US. In 1792, he constructed a circus building in Philadelphia. Twelve months later he gave America's first hooves 'n all circus performance. George Washington himself is believed to have seen at least one of his shows.

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Dan Rice (1823–1900) - America applauded this new form of entertainment. The equestrian company of Pepin and Breschard became the first American circus, and Dan Rice became the country's best-known pre-Civil War clown. He coined the expression "One-Horse Show."

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Phineas Taylor Barnum (1810 –1891) - The man who revolutionized the American circus was P.T. Barnum, a name synonymous with brazen showmanship and questionable ethics.

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Barnum & Bailey Greatest Show on Earth - Barnum had already established his "Travelling Menagerie" with business partner William Cameron Coup. But it was his Barnum & Bailey Greatest Show On Earth, co-founded with James Bailey, that put the traveling circus on the world map.

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James Anthony Bailey (1847–1906) - Born James Anthony McGinnis in Detroit, the American circus ringmaster worked with P.T. Barnum to present the public with acts similar to those offered by the "Travelling Menagerie"—acrobats, exotic animals, and so-called "freak shows."

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Jumbo the Elephant - The show's first big crowd-puller was Jumbo, a huge African elephant. The giant beast's name later spawned the common word "jumbo," meaning large in size.

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The Greatest Show on Earth - Barnum was one of the very first circus owners to move his circus by train. Not only was this a more convenient way to travel, it proved a shrewd business move, extending the showman's reach across the states he toured.

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The Greatest Show on Earth - Audiences were left wide-eyed in awe at the skills of graceful trapeze artists and other high-wire acts.

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Freak show characters - Barnum's "freak shows" presented an array of different characters such as General Tom Thumb and fellow little person, Commodore Nutt (pictured). The cast also included the conjoined twins, Chang and Eng, and 2.41-m (7 ft, 11-in) Anna Swan, the "giantess."

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Sells Brothers Circus - As the 19th century progressed, circuses in the US, like Sells Brothers Circus, based out of Columbus, Ohio, started experimenting beyond the traditional equestrian acts of old. Notably, circus owners began using other animals in set pieces.

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The circus comes to town - The American circus format was soon adopted by circuses based in Europe and beyond. Animals, the more dangerous the better, were increasingly becoming the stars of the show.

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Animal acts - Exotic big cats, usually lions and tigers, were trained by so-called "lion tamers" to perform stunts to please an increasingly demanding audience.

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Isaac A. Van Amburgh (1808–1865) - In 1833, animal trainer Van Amburgh entered a cage containing several big cats and subsequently developed the first trained wild animal act in modern times.

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Animal welfare - Animals are still used in some circus acts today, although the practice has been shamed by animal welfare groups such as PETA. In many countries there are nationwide bans on using some (if not all) animals in circuses. These days, in response to a growing concern about the use of animals in entertainment, animal-free circuses are becoming more common around the world.

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The circus in popular culture - One of the most famous references to the traditional circus alluded to Pablo Fanque's Circus Royal from 1843. The poster advertising the event inspired the Beatles' song 'Being for the Benefit of Mr. Kite!' which appeared on their 1967 album 'Sgt. Pepper's Lonely Hearts Club Band.'

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Contemporary circus - Today, contemporary circus focuses more on aesthetic impact. While still combining traditional acrobatic circus skills and theatrical techniques, emphasis is also placed on lighting and costume design, original music, and stunning visuals. Pictured is the 'Human Candelabra,' a member of the Chinese State Circus.

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Moscow State Circus - Moscow State Circus acrobat Vlad Khvostik making it look easy.

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Circus Circus Las Vegas -

Circus Circus Las Vegas is a hotel and the largest permanent big top in the world. The hotel's famous circus routines featured prominently in the James Bond adventure 'Diamonds are Forever' (1971).

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International Circus Festival of Monte Carlo - An annual event held since 1974, the International Circus Festival of Monte Carlo brings together the best circus acts in the world.

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International Circus Festival of Monte Carlo - The star-studded festival is staged in a competition format, with awards for the most daring and innovative circus skills. There is also the prestigious Clown d'Or (Golden Clown) award up for grabs.

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Cirque Du Soleil - The circus for the modern era, and one that continually redefines the contemporary genre, is Canada-based Cirque du Soleil.

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Cirque du Soleil - Founded in 1984, Cirque du Soleil has gone from one show to more than 20 different shows in over 271 cities on every continent except Antarctica.

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Cirque du Soleil - Always blending acrobatics, aerial acts, and stage floor theatrics from an international cast that averages over 50 performers, the company's creations have garnered numerous awards, prizes, and distinctions.

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Oleg Popov (1930– 2016) -

A cherished member of any circus troupe is the clown, because everybody loves to laugh. Soviet and Russian circus artist Popov was the funniest of them all.

See also: Clown curiosities: the crazy, the quirky, and the downright creepy

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