If one painting can honestly claim to have changed the course of art history, it is Picasso’s “Demoiselles d’Avignon,” which turns 100 this year. Centenarian and eternally young, it is the prism through which streamed all the most advanced tendencies in European art around 1900, only to be refracted in an entirely new synthesis whose influence was incalculable.

The genesis of this famous painting is the subject of a focus exhibition at the Museum of Modern Art, which has owned the work since 1939. The show comprises 12 drawings, watercolors, and oils, from MoMA’s own collection as well as the Musée National Picasso in Paris and various private collections.

Splendidly displayed in the galleries of the Modern, “Les Demoiselles d’Avignon” is surely an iconic image, but not like the “Mona Lisa.” Most of us can no longer quite see the latter, because it has been disseminated so widely and so often. But Picasso’s painting, with its five figures and foregrounded still-life, is sufficiently multiform that, however well you know it, you want to look at it again. It is not a lovable or an especially beautiful work. Surely we are no longer shocked by its open sexuality or its invoking the savage elements of human nature. And yet, it remains what it is, the depiction of a brothel in Barcelona by a rebellious and famously oversexed 26-year-old. In no small measure, formal and thematic provocation is its entire point.

Five women stand or crouch before a curtain drawn aside, offering themselves to you the viewer. As we learn from a preliminary sketch, one of many that Picasso made in the winter of 1906 and 1907, the original idea was to include two sailors along with the women. But Picasso apparently felt that their presence, with its intimation of narrative, would distract from his larger purpose, especially from his full frontal address of the viewer.

The title, which was not Picasso’s idea but probably André Salmon’s, refers to a street in Barcelona famous for its houses of ill-repute. The title’s effetely Symbolist medievalism was doubtless a joke intended to accentuate the true coarseness of the subject matter.

As so often with the cardinal works of art history, there is little in the painting that cannot be traced to the art of the generations that preceded it. The depiction of prostitutes — as one of the preoccupations of the Modern movement — looks back to Courbet, Manet, and Baudelaire. While the harshly facetted treatment of the figures — which would evolve two years later into Analytic Cubism — recalls Cézanne, the painting’s chromatic chaos and its obliteration of one-point perspective had been made feasible by Gauguin in his second visit to Brittany, and the last links to retinal reality had already been severed, a few seasons earlier, by Matisse and the first of the Expressionists.

But even when we take all of that into account, nothing that precedes “Les Demoiselles d’Avignon” quite matches its power or its impact. Like Giotto in 1300, Masaccio in 1425, and Caravaggio in 1600, Picasso in 1907 created an entirely new way of conceiving the human form in two dimensions. But unlike those predecessors, who challenged the formal, but not the cultural assumptions of their ages, Picasso gave pictorial expression to a new way of thinking and feeling about man and his relation to society.

What appears to be uniquely Picasso’s contribution to art history at this point — beyond the potent synthesis of his predecessors — was the introduction of African art, and more importantly, the spirit and the formal lessons of African art, into the heart of Western culture. Whereas van Gogh learned from Japan and Gauguin from Polynesia, they had easily accommodated the artifacts of those societies to a Western context. In Picasso’s case, it is the African element that, for the first time, gains the upper hand. That was the most shocking and revolutionary fact about “Les Demoiselles d’Avignon.”

Today we are no longer sure what it means for Western culture to be Western. In 1907, there was no doubt, nor was there any doubt that Picasso had disrupted that order. Perhaps Western culture was heading in this direction all along, just as Occidental mariners, in the late 1400s, were floating, without realizing it, ever closer to North America. Picasso, like Columbus, was the first to arrive in the New World, after which the voyage became easy, then expected, and finally, almost obligatory.

It is one of the oddities of art history that Picasso himself did not fully exploit the cultural implications of this new development for nearly a generation. Formally, the break with retinal reality that was promulgated in “Les Demoiselles d’Avignon” led to Cubism. But that in turn gave way, around 1916, to the supremely Eurocentric neoclassicism of his “Ballets Russes” period. From there, he moved on to surrealism and only in the ’30s, with “Guernica” and his depictions of the Minotaur, did the artist, now middle-aged and world famous, return to the destabilizing implications of his early masterpiece. In them, he found the guidance for that unstinting torrent of art that he would create up to the very end of his long life.

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