As an art-history term of art, Modernism is focused on a period in western art from the 1860s through the 1970s. The word is difficult to define because it embraced the state of mind of being non-traditional, which meant that a variety of emerging styles came under the label, especially if the rebellion was against current standards espoused by the National Academy of Design in New York City---regarded as a "coterie of conservative artists." Early 'modernists' artists such as Gustave Courbet, Paul Cezanne and Edouard Manet in France rebelled against tradition by depicting contemporary life instead of historical subjects. When Modernism came to America, it was shaped by much of what was going on in Europe, especially with Impressionism at the turn of the 19th Century. Modernism took hold full force with the introduction of Cubism, Futurism and other isms at the 1913 Armory Show in New York City, and was then followed by the Social Realists. Led by Robert Henri, likely the most potent force behind the push to free art expression, from the Academy, he and his AshCan School painters dealt with 'indelicate' subjects such as street people, prostitutes and other victims of American poverty. A major factor in opening the door to Modernism was the withdrawing of sponsorship and control of the arts by the Catholic Church, governments and aristocrats. Many of the themes of modern art were based on the new industrialism and secularism because technology and challenges to middle-class values increasingly displaced formal religion. Sources: Robert Atkins, "Art Speak"; Martha Severins, 'What Modern Looked Like', "American Art Review", November 2005, p. 126; Arrell Morrill Gibson, "The Santa Fe and Taos Colonies"