October Painting, first recorded in Indiana's journal entry for October 31, 1959, was inspired by the shadows of his corn plant (dracaena). In the entry the artist notes that the painting was a return to working in free-form, which he had negelcted since "Jack Youngerman's arrival on the scene." He explains that he was influenced by Ellsworth Kelly's 1957 painting Orange Peel [Orange Blue], as well as "dormant experiments with a flowing hard edge," "a digging back into the botany days of Scotland [where he studied at the University of Edinburgh]," and the Akira Kurosawa film Rashoman, which he had seen the previous evening.
Indiana's journals indicate that he returned to the work in December of that year, first on the 3rd and then on the 31st. In the latter entry he describes the work as a "very seminal painting."
October Painting remained in the artist's collection until his death, and was first exhibited in 2025, in the show Robert Indiana: The Source, 1959–1969, at Kasmin Gallery, New York.