Impression, Sunrise, Claude Monet, 1872
Began in France (Paris specifically) in the mid-late 19th century before spreading and inspiring various different impressionist movements in other countries. Lasted in its heyday from roughly the 1860s to the 1890s. The name was originally inspired by the Monet painting "Impression, Sunrise" (as shown above). The impressionists' focus on painting based around sensory perception, rather than objective reality, helped lay the groundwork for several other radical and avant-garde art movements to develop through the 20th century and beyond.
"Encompassing what its adherents argued was a different way of seeing, it is an art of immediacy and movement, of candid poses and compositions, of the play of light expressed in a bright and varied use of colour."
"Radicals in their time, early Impressionists violated the rules of academic painting. They constructed their pictures from freely brushed colours that took precedence over lines and contours, following the example of painters such as Eugène Delacroix and J. M. W. Turner. They also painted realistic scenes of modern life, and often painted outdoors. Previously, still lifes and portraits as well as landscapes were usually painted in a studio. The Impressionists found that they could capture the momentary and transient effects of sunlight by painting outdoors or en plein air. They portrayed overall visual effects instead of details, and used short "broken" brush strokes of mixed and pure unmixed colour—not blended smoothly or shaded, as was customary—to achieve an effect of intense colour vibration."
"The group was unified only by its independence from the official annual Salon, for which a jury of artists from the Académie des Beaux-Arts selected artworks and awarded medals. The independent artists, despite their diverse approaches to painting, appeared to contemporaries as a group. While conservative critics panned their work for its unfinished, sketchlike appearance, more progressive writers praised it for its depiction of modern life."
"Claude Monet’s Impression, Sunrise (Musée Marmottan Monet, Paris) exhibited in 1874, gave the Impressionist movement its name when the critic Louis Leroy accused it of being a sketch or “impression,” not a finished painting."