The shift to modernism can be partly credited to new freedoms enjoyed by artists in the late 1800s. Traditionally, a painter was commissioned by a patron to create a specific work. The late 19th century witnessed many artists capable of seizing more time to pursue subjects in their personal interest.

At the same time, the growing field of psychology turned the analysis of human experiences inward and encouraged a more abstract kind of science, which inspired the visual arts to follow.

With shifts in technology creating new materials and techniques in art-making, experimentation became more possible and also gave the resulting work a wider reach. Printing advances in the late 1800s meant posters of artwork widened the public’s awareness of art and design and ferried experimental ideas into popular culture.

Officially debuting in 1874, Impressionism is considered the first Modernist art movement. With leaders like Claude Monet and Pierre-Auguste Renoir, the Impressionist's use of brief, fierce brush strokes and the altering effect of light separated their work from what came before it. The Impressionists’ focus on modern scenes was a direct rejection of classical subject matter.

Subsequent movements such as Post-Impressionism, Fauvism, Cubism, Constructivism, and De Stijl were just a sampling of those following the experimental path started by Impressionism.

The Dada movement took experimentation further by rejecting traditional skills and launching an all-out art rebellion that embraced nonsense and absurdity. Dadaist ideas first appeared in 1915, and the movement was made official in 1918 with its Berlin Manifesto.

French artist Marcel Duchamp exemplified the haughty playfulness of the Dadaists. His 1917 piece Fountain, a signed porcelain urinal, and his 1919 L.H.O.O.Q., a print of Leonardo da Vinci’s Mona Lisa with a mustache penciled over it, both turn their back on the very idea of creating art. In doing so, Duchamp predicted Post-Modernism.

Modernism reached its peak with Abstract Expressionism, which began in the late 1940s in the United States. Moving away from commonplace subjects and techniques, Abstract Expressionism was known for oversized canvasses and paint splashes that could seem chaotic and arbitrary.

Each Abstract Expressionist work functioned as both a document of the artist’s subconscious and a map of the physical movements required to create the art. Painter Jackson Pollack became famous for his method of dripping paint onto canvas from above.

The transition period between Modernism and Post-Modernism happened throughout the 1960s. Pop Art served as a bridge between them. Pop Art was obsessed with the fruits of capitalism and popular culture, like pulp fiction, celebrities and consumer goods.

Begun in England in the late 1950s but popularized in America, the movement was informed by former Abstract Expressionists like Jasper Johns and Robert Rauschenberg, who had metamorphosed into the Neo-Dada movement of the late 1950s.

Rauschenberg’s 1960 sculpture of Ballantine Ale cans pre-dated Pop artist Andy Warhol’s famous Campbell’s Soup cans. Warhol gained further fame from his haunting silkscreen portraits, most famously of celebrities such as Marilyn Monroe, while Pop Art compatriot Roy Lichtenstein plundered comic book panels for his paintings.

Post-modernism, as it appeared in the 1970s, is often linked with the philosophical movement Poststructuralism, in which philosophers such as Jacques Derrida proposed that structures within a culture were artificial and could be deconstructed in order to be analyzed.

As a result, there was little to unite Post-Modern art other than the idea that “anything goes” and the preponderance of unusual materials and mechanical processes for expression that feel impersonal, though often employing humor.

At the heart of Post-Modernism was conceptual art, which proposed that the meaning or purpose behind the making of the art was more important than the art itself. There was also the belief that anything could be used to make art, that art could take any form, and that there should be no differentiation between high art and low art, or fine art and commercial art.

Post-modern work in the 1970s was sometimes derided as “art for art’s sake,” but it gave rise to the acceptance of a host of new approaches. Among these new forms were Earth art, which creates work on natural landscapes; Performance art; Installation art, which considers an entire space rather than just one piece; Process art, which stressed the making of the work as more important than the outcome; and Video art, as well as movements based around feminist and minority art.

The 1980s saw the rise of appropriation as a much-used practice. Painters like Jean-Michael Basquiat and Keith Haring directly mimicked graffiti styles, while artists like Sherrie Levine lifted the actual work of other artists to use in their creations. In 1981, Levine photographed a Walker Evans photo and represented it as a new work questioning the very idea of an original photo.

Post-modern art has since become less defined by the form the art takes and more determined by the artist creating the work. American artist Jenny Holzer, who came to prominence in the 1970s with her conceptual art made from language, embodies this model.

Holzer’s “Truisms” are deceptively simple sentences that communicate complicated, often contradictory, ideas, such as “Protect me from what I want.” She has also produced a body of work on the American government’s use of torture during the Iraq War. Holzer’s curation of text, rather than any visual motif, is the consistent aspect uniting her work.

Some art historians believe the Post-Modern era ended at the beginning of the 21st Century and refer to the following period as Post Post-Modern.

History of Modern Art. H.H. Arnason and Marla F. Prather.
Modern Art: Impressionism To Post-Modernism. Edited by David Britt.
Art of the Western World. Michael Wood.
What Is Modern Art? Metropolitan Museum of Art.
Modernism. Tate.