William H. Johnson was an African-American painter and printmaker; he was born in Florence, South Carolina in 1901 and studied art in New York, Massachusetts, and in Europe, before returning to the States for the remainder of his career. This is from a series of woodcuts and linoleum prints that bear a strong folk art influence but, says the Smithsonian commentary, were also inspired by German expressionist woodcutting techniques. I'm guessing the apparent left-handed guitar and violin technique is an artifact of the mirror-image printing process, though this other lovely print would beg to differ.