Mpls, MN - John Thomas Kemper, age 81, of Minneapolis, died January 9, 2026 at home from complications of Parkinson's Disease.

He is survived by his wife of 58 years, Sallie Lancaster Kemper; daughters Anne Mason Kemper (Keith Johns) and Sara West Kemper (Sean Boley); granddaughters Iona, Ivy, Maeve, and Adrian; brother Donald Kemper (Molly Mettler), sister Martha Lee Kemper (Jean Brophy), and many nieces and nephews. He is preceded in death by his parents, Dorothy Chappuis Kemper and Walter Rice Kemper, and sister, Karen Kemper Magee.

John was born on March 7, 1944 in San Francisco, CA, where his father was stationed during World War II. He spent most of his childhood in Corpus Christi, Texas, before moving to Houston. He graduated with honors from Bellaire High School in 1962, where he lettered in basketball and was editor of his high school yearbook. John graduated magna cum laude from Rice University with a B.A. in mathematics in 1966 and was named to Phi Beta Kappa. He went on to earn a Ph.D., also at Rice, in 1970.

John and Sallie first moved to Minneapolis in 1968 to follow John's Ph.D. thesis advisor, and returned in 1974 after four years in New York City, where John taught at New York University and the City College of New York. They eventually settled in St. Paul, where they raised their family.

John spent most of his career as a Professor of Mathematics at the University of St. Thomas, where he retired with emeritus status in 2011. He was a demanding yet encouraging teacher and mentor, earning the University's Professor of the Year award in 2001. During his 35-year tenure at St. Thomas, John served several terms as math department chair, received multiple NIH and NSF research grants, and helped found the Center for Applied Mathematics and the Actuarial Science Program.

Above all, John was a devoted husband, father, and grandfather. He was a lifelong advocate for girls and women, especially in mathematics, science, business, and sports. An avid gardener and environmentalist, John loved being outdoors, spotting wildlife, canoeing, camping, and fishing. He advised us to "take care of the living things first."

He will be remembered at a private gathering later in the year. Memorials may be directed to Emily's List, the Michael J. Fox Foundation, or Friends of the Boundary Waters.