Abstract Expressionism is a style of painting that combines abstract form and expressionist emotional value. It started in the mid 1940’s in New York but its influence comes much earlier from Surrealism and Cubism. It is often considered America’s most important contribution to Modernism.
This was a post-World War II movement out of New York City. The movement is not solely characterized on the fact that all artists associated were abstract or expressionist. Rather, the movement had a number of styles. It can be said that it is an approach that involves complete freedom from all traditional aesthetic and social values and favors spontaneous, free personal expression.
“The big moment came when it was decided to paint 'just to paint'. The gesture on the canvas was a gesture of liberation from value — political, aesthetic, moral." - Harold Rosenberg, art critic
“I don't understand it. Jack will spend any amount of money to buy votes but he balks at investing a thousand dollars in a beautiful painting.” - Jackie Kennedy
“The crucial discovery was made that, in order to become painting, the universe seen by the artist had to become a private one created by himself." - André Malraux, French author, adventurer, and statesman
"The secret to so many artists living so long is that every painting is a new adventure. So, you see, they're always looking ahead to something new and exciting. The secret is not to look back.” - Norman Rockwell
Hans Hoffman (1880 – 1966) painter who has been called a Fauvist, Cubist, and Abstract Expressionist often known as the “father” of abstract expressionism. In 1934 he founded the Hans Hoffman School of Fine Arts in New York City influencing artists such as Lee Krasner and Robert de Niro.
Pablo Picasso (1881–1973) impacted the development of modern and contemporary art with a prolific output including over 20,000 paintings, prints, drawings, sculptures, ceramics, theater sets and costumes. His creative styles transcend realism and abstraction, Cubism (created by Picasso and Georges Braque in Paris between 1907 and 1914), Neoclassicism, Surrealism, and Expressionism.
Willem De Kooning (1904 – 1997) born in Rotterdam, the Netherlands, painted in the style that is referred to as Abstract Expressionism, Action painting, and the New York School. His vintage works drew increasing profits; in a private sale Woman III (1953) sold for US$137.5 in 2006. 
Lee (Lena) Krasner (1908-1984) born in Brooklyn to Russian-Jewish immigrants, she became one of the influential abstract expressionists in the second half of the 20th century. Married to Jackson Pollock in 1945, Krasner was rigorously self-critical, and her critical eye is believed to have been important to Pollock's work.
Franz Kline (1910-1962) was an American painter mainly associated with the Abstract Expressionist painters who were centered, geographically, around New York, and temporally, in the 1940s and 1950s.
Jackson Pollock (1912–1956) an American Abstract painter known as “Jack the Dripper” for his unique drip technique. In November 2006 Pollock's "No. 5, 1948” became the world's most expensive painting, when it was auctioned to an undisclosed bidder for the sum of $140,000,000. 
Gino Hollander (born 1924) one of the most prolific American painters, self-taught in NYC’s Greenwich Village at the age of 38, after quitting a successful career in filmmaking. Hollander's work exemplifies the emotional intensity of the German Expressionists, part of which from this movement was based on.
Jasper Johns (born 1930) a contemporary American artist of painting and printmaking, is one of most significant and influential American painters of the twentieth century. Johns holds the honor of “Most expensive painting by a living artist” $80 million in 2006.
 “What is Abstract Expressionism." Jackson Pollock Unauthorized. 15 January 2008.
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