Diana Denise Downing Mashburn

Diana Denise (Downing) Mashburn passed peacefully from this life to the next on February 11, 2026 in Oklahoma City. She was born on May 14, 1965, to Charles and Mary Downing of Muskogee, Oklahoma. She graduated from Muskogee High School in 1983. Diana was an Associate Professor of the Anna Vaughn School of Nursing at Oral Roberts University in Tulsa. She considered this her supreme professional accomplishment: Coming full circle to be a faculty member since her undergraduate college experience began at ORU as a pre-med student. After changing her major to Nursing, she earned an Associate of Arts from Bacone College, a Bachelor of Science in Nursing from Northeastern State University, and a Master’s of Science in Nursing from the University of Oklahoma. Diana completed a Ph.D. in Nursing from the University of Minnesota in 2012, becoming a member of an elite group. At that time, Dr. Mashburn became one of fewer than 15 Native American nurses in the United States holding this doctoral credential. Board-certified as a Medical-Surgical Nurse and Certified Nurse Educator, she taught nursing at nearly every level, from Certified Nurse Assistant to doctoral levels. She filled the role of Director of Nursing at Northeastern State University and Director of Nursing and Allied Health for Connors State College. She has served as a Peer Evaluator for the Accreditation Commission for Education in Nursing. Diana held leadership positions in the Oklahoma Nurses Association, the Oklahoma Indigenous Nurses Association, and the Zeta Delta Chapter of Sigma Theta Tau. In July of 2018, Diana was selected by Northeastern State University to travel to Beijing, China to meet with nursing educators and students to compare notes and offer her professional advice on these programs. She was also a regular volunteer at Muskogee's Baptist Free Health Clinic. Diana belonged to Muskogee Hope Chapter No. 401 Order of the Eastern Star. She served the Oklahoma Grand Chapter as Grand Lecturer in 2017. Diana was a member of the Muskogee-Indian Territory Chapter of the Daughters of the American Revolution, Veterans of Foreign Wars of the United States Auxiliary, Post 474 Muskogee and the Clement A. Evans Chapter, United Daughters of the Confederacy, Tulsa. Diana worshipped at Grandview Baptist Church in Muskogee alongside her husband, Greg Mashburn. The couple had no children but shared a love for their “fuzzy love puppy”, Usdi. Diana was preceded in death by her father, Charles Downing and her grandmother, Willie Jestice. She is survived by her husband Greg; mother, Mary (McLain) Downing; sister, DaRhonda (Downing) Clabaugh; brother-in-law, Seth Clabaugh; nephew, Matthew Clabaugh and his wife Morgan (Beal) Clabaugh; and niece, Mary Dawn Clabaugh. Diana’s life will be remembered at 10AM, Thursday, February 19, 2026 at Grandview Baptist Church with Brother Jay McAlister and Dr. Danny Mills officiating. In lieu of flowers, the family prefers nursing scholarship donations in Diana’s name to Oral Roberts University in Tulsa, Connors State College in Warner or Northeastern State University in Tahlequah.

Diana Denise Downing Mashburn

May 14, 1964 - February 11, 2026