Gertrude Stein is an avant-garde author and cultural figure born in 1874 to upper-middle-class parents. After leaving medical school at Johns Hopkins, she relocates to Paris. She builds a reputation by acquiring a significant art collection and hosting cultural events for prominent artists. In her writing, she applies Cubist techniques to language to defy conventional syntax.

Alice Toklas is Gertrude Stein's lifelong romantic partner. She lives with Stein in Paris, sharing in the vibrant cultural environment of the early 20th century. Her relationship with Stein serves as an inspiration for the erotic and domestic themes present in experimental texts like Tender Buttons.

Pablo Picasso is a painter in the Cubist movement and a prominent figure in the Parisian art world. He breaks concrete forms into intersecting planes, participating in the avant-garde aesthetic shifts of the era. His artistic experimentation directly influences contemporary literary techniques.

Juan Gris is a painter and early practitioner of the Cubist movement. He operates within the same artistic circles as Stein, contributing to the visual theories that eventually alter the trajectory of Modernist poetry.

William James is an influential thinker and educator at Harvard University. He provides academic instruction to Stein during her undergraduate years. His teachings contribute to her early intellectual development before she turns to medicine and eventually art.

Ernest Hemingway is a prominent author active in the early-20th-century Parisian cultural scene. He participates in the artistic network fostered by Stein's gatherings.

F. Scott Fitzgerald is a writer who participates in the cultural events hosted by Stein in Paris. He acts as part of the broader artistic network surrounding the author.

Ezra Pound is a literary figure operating within the Parisian cultural scene. He interacts with the avant-garde community that Stein actively cultivates.

Henri Matisse is an artist who takes part in the cultural gatherings organized by Stein. He forms part of the visual arts community that indirectly influences literary experimentation.