John French Sloan was born on August 2, 1871 in Lock Haven, Pennsylvania to James Dixon and Henrietta Sloan. John French Sloan grew up and lived in Philadelphia, Pennsylvania until 1904.

In 1888, Sloan's father experienced a mental breakdown that left him unable to work. Sloan became responsible for financially supporting his family by working as an assistant cashier at Porter and Coates, a bookstore and seller of fine prints. It was there, Sloan created his earliest surviving works, among which are pen and ink copies after Dürer and Rembrandt. He also began making etchings that were sold in the store he was working for. In 1890, Sloan was offered a position to work for A. Edward Newton at a stationery store. While working at Newton's, Sloan created greeting cards and calendars and he continued to work on etchings. He also attended the Spring Garden Institute, which provided him his first formal art training.

In 1892, Sloan began working as an illustrator in the art department of The Philadelphia Inquirer. He also met a talented painter and charismatic advocate of artistic independence, Robert Henri. Robert Henri encouraged Sloan to turn to painting in the form of realism. Sloan left The Philadelphia Inquirer for The Philadelphia Press, which freed up his schedule to paint more.

John married Anna Maria in 1905 and they moved to New York City, and he had become much more financially stable drawing illustrations for books and for journals such as Collier's Weekly, Good Housekeeping, Harper's Weekly, The Saturday Evening Post, and Scribner's.

Sloan participated in the landmark 1908 exhibition at the Macbeth Galleries with a group that included four other artists from the Philadelphia Charcoal Club. In 1917, Sloan had a one-man show at Kraushaar's in New York, a gallery he maintained a lifelong connection with. A year later he was named president of the Society of Independent Artists, a position that he held until his death.

In 1943, Dolly Sloan died of coronary heart disease and a year later John Sloan married Helen Farr, whom he met at the Art Students league. He and his new wife spent the summer of 1951 in New Hampshire, which was discouraged by his doctor. Sloan died on September 7, 1951 from cancer while vacationing in Hanover, New Hampshire. The Whitney Museum of American Art presented a retrospective of his career the following January. His wife, Helen Farr Sloan became a noted philanthropist in her later years, and she oversaw the distribution of his unsold works to major museums throughout the country.