Final answer:
Landscapes became a significant subject matter in American art as the continent was explored and settled, marking a shift from European influence and the introduction of American Realism.
Step-by-step explanation:
As the continent was being explored and settled, landscapes replaced natural still-lifes and scenes of everyday life as subject matter. Landscape painting, which was not initially revered in the European or American art traditions, became popular in the 1800s due to the works of artists like John Constable. His depictions of the region around his home set the stage for the American landscape painters who captured the striking vistas of the American westward expansion. This shift towards landscape art marked a movement away from European influences as artists began to celebrate the distinct natural beauty found in America. Furthermore, this period saw the rise of American Realism, with artwork representing democracy, heroic American life, and westward expansion, diverging distinctly from European focus on religious art or paintings of royalty. After the Civil War, there was a surge in photography, prints, and magazine illustrations as popular expressions of art, influenced by the changing American landscape and society.