William Langson Lathrop was an American Impressionist landscape painter and founder of the art colony at New Hope, Pennsylvania. He is sometimes referred to as a "Pennsylvania Impressionist". Lathrop was a member of the National Academy of Design and served on numerous exhibition juries during his career. He received a gold medal at the Panama–Pacific International Exposition in San Francisco, California, which showcased works by many of the major American artists of the time. Today, Lathrop's paintings are in numerous museum collections including the Metropolitan Museum of Art in New York City, and the Smithsonian American Art Museum in Washington, D.C.