Described as ugly and barbaric in its own time, everyone today agrees it's Matisse's best.

Matisse got a vague commission from one of his best patrons for two large works to decorate the entryway of a palace. The patron in question was Sergei Shchukin: textile magnate and Russian business mogul. Shchukin started at the bottom and got to the top by scooping up all the cloth-making materials he could during the terrible 1905 Revolution and then jacking up the price when everyone had money again. Shchukin wasn't a terrible guy...necessarily. He'd let the public into his home to view his art collection once a week, with a particular affinity for getting poor art students in front of the art so they could practice their craft.

The specific idea for Dance came from a visit by Matisse and Shchukin to Picasso's studio to view his brand spankin' new Les Demoiselles d'Avignon. Matisse's Dance just took the five nude-y people and put them in a circle. The dancer at the top left might be a coy self-portrait of Matisse. He'd often doodle a cartoon of himself on postcards or in the middle of a document, and the figure's boobies and paunch look kind of like his glasses and nose in those sketches. It's one of those optical illusions you can't see until you do, and then disturbingly can't un-see. 

Shchukin almost nixed the project midstream when he found out Matisse was planning to put ten foot tall hippies in a dance circle at his palace's grand entrance. But he sacked up and got a, "To hell with them," attitude. Impressionism and modern art weren't exactly haute couture in Russia at the time, and wouldn't be for decades. Shchukin couldn't care less about what other people liked, though, and amassed a collection of several hundred paintings that included almost 40 by Matisse and more than 50 by Picasso. Shchukin liked that impressionism and modernism was bold and new and unlike anything else around. He may have been the world's first hipster.

Then, World War I caused belts to collectively tighten. Shchukin decided to stop collecting art for a while (not like he had a choice), unknowing that he'd never be able to do it again. As the Great War ended, revolution swept Russia and made the wealthy and nobility either run for their butts or get hacked to pieces. Shchukin ran, leaving behind almost everything. Including his art collection, which was absorbed into the Soviet Union in trust for the people. Shchukin moved to Paris. When Matisse found out Serge was in town, he kept hitting up the former mogul for cash. Shchukin ducked the artist's calls at first, and eventually wrote him off as a friend altogether.