Realist painter and illustrator who helped to establish the Ashcan School of American art. He assisted Albert C. Barnes in setting up the Barnes Foundation in Philadelphia.
He studied at the Pennsylvania Academy of Fine Arts and worked as an artist and reporter for The Philadelphia Record. He was then hired as an illustrator for the Philadelphia Press. He studied with realist Thomas Anshutz at the Pennsylvania Academy of the Fine Arts.
His 1912 painting "Italo-American Celebration, Washington Square" was displayed at the Boston Museum of Fine Arts.
He was born into a family that had lived in Philadelphia for generations. He grew up with older sister Ada and older brother Louis Glackens, who would become a famous cartoonist and illustrator. He married artist Edith Dimock in 1904.
His work was compared to that of Pierre Auguste Renoir.