• Painter Thomas Pollock Anshutz, 1851

In 1876 Anshutz and Thomas Eakins joined the Pennsylvania Academy of the Fine Arts. Eakins became Chief Demonstrator of Anatomy while Anshutz continued as his student, and the student of Christian Schussele. In 1878 Anshutz became Eakins assistant, eventually replacing Eakins as Chief Demonstrator when Eakins became Professor of Drawing and Painting. In 1880 he completed his first major work, Ironworker's Noontime, while still a student.

Ironworker's Noontime, Anshutz's most well known painting, depicts several workers on their break in the yard of a foundry. Painted near Wheeling, West Virginia, it is conceived in a naturalistic style similar to that of Eakins, although Eakins never painted industrial subjects. The piece was exhibited at the Philadelphia Sketch Club in 1881 and compared to Eakin's work by art critics. Art historian Randall C. Griffin has written of it: "One of the first American paintings to depict the bleakness of factory life, The Ironworkers' Noontime appears to be a clear indictment of industrialization. Its brutal candor startled critics, who saw it as unexpectedly confrontational — a chilling industrial snapshot not the least picturesque or sublime." It is now in the collection of the Fine Arts Museums of San Francisco.

Around 1880 Eakins became involved in photography, incorporating it into his classes and artwork. Anshutz and other artists at the Academy started to make use of the camera, posing models and students to take photos and making prints for study. Anshutz participated in Eakins The Naked Series, creating photographs featuring nude models in seven predefined standing poses. He also participated by modeling as well, along with other colleagues like Eakins, John Laurie Wallace and Covington Few Seiss, who would pose outdoors nude, often wrestling, swimming and boxing. Eadweard Muybridge eventually made his way to Philadelphia and Anshutz and Eakins helped build Muybridge's zoopraxiscope. Eakins was dismissed from his position in 1886 and Anshutz took over as art instruction leader at the Academy. Anshutz would briefly travel to Europe, focusing primarily on his teaching in Philadelphia. Numerous artists studied under Anshutz, including George Luks, Charles Demuth, John Sloan, Charles Sheeler, Everett Shinn, John Marin, William Glackens and Robert Henri. As a teacher, Anshutz, according to art historian Sanford Schwartz, "was known as much for his approachability as his sarcasm, which apparently wasn't of the withering variety."

The Anshutz family regularly vacationed in Holly Beach, New Jersey, which served as a creative place for the painter. There he experimented with watercolors, bright color palette and simple compositions. He also photographed the natural environment, utilizing the images as studies for paintings, specifically Holly Beach and trips down the Delaware and Maurice rivers. Although Anshutz experimented persistently with landscape painting, he was better known for his portraiture, which won him numerous awards in the 1890s and 1900s. In 1898 he and Hugh Breckenridge co-founded the Darby School, a summer school outside of Philadelphia which emphasized plein air painting. At Darby Anshutz created his most abstract works, a series of bright oil landscape paintings that were never exhibited. He continued to participate at Darby until 1910. He served as a member of the National Academy of Design and president of the Philadelphia Sketch Club.

In 1971 Robert and Joy McCarty, who lived in the home formerly owned by the Anshutz family in Fort Washington, Pennsylvania, donated a portion of letters, glass negatives and photographs to the Archives of American Art. A second donation from the Anshutz family took place in 1971 and 1972, which were microfilmed and returned to the family.