(studied painting under several notable artists ) at the National Academy of Design and the Art Students League. Among his teachers were Frank Vincent DuMond and George de Forest Brush. But Hawthorne declared that the most dominant influence in his career was William Merritt Chase, with whom he worked as both a pupil and assistant. Both men were naturally talented teachers and figurative painters who were drawn to rich color and the lusciousness of oil paint as a medium. Chase passed on a Munich tradition of tone values and tone painting, and Hawthorne learned all he could.

The Cape Cod School of Art was the first outdoor summer school for figure painting and grew into one of the nation's leading art schools. Under thirty years of Hawthorne's guidance, the school attracted some of the most talented art instructors and students in the country including John Noble, Richard Miller, and Max Bohm. At his school, Hawthorne gave weekly criticisms and instructive talks, guiding his pupils and setting up ideals but never imposing his own technique or method.