 Although she was active in the early decades of the 20th century when Native American art and Art Nouveau were making a parallel climb into mainstream fine art exhibitions, Sully was considered revolutionary in marrying these two genres.Susan Mable Deloria was born to father Tipi Sapa (Black Lodge), or Philip J. Deloria, and mother Mary Sully.She is the great-granddaughter of 19th century American portrait artist Thomas Sully, from whom she took her name.