Rosen grew up in Westmoreland County in western Pennsylvania and moved to New York to enroll in painting classes at the National Academy of Design. He studied with William Merritt Chase. In 1903, he moved to New Hope and enjoyed the camaraderie of Daniel Garber, Edward Redfield, William Lathrop, and John Folinsbee. After 1920, the artist moved permanently to Woodstock, New York, where he served as director of the Art Students League Summer School.
