Glenn A. Thiel, MD, 70, of Marinette County, WI, passed away on Thursday, May 7, 2026.

He was born on August 5, 1955, in Green Bay, WI, to the late Alfred F. and Ruth M. (Winkler) Thiel.

Glenn graduated from Green Bay West High School, class of 1973. He received his Bachelor of Science Degree in Zoology from the University of Wisconsin, Madison, in 1977, where he graduated Magna Cum Laude. He received his Medical Degree from the Medical College of Wisconsin in 1982.

Glenn completed the National Board Exam and residency in Emergency Medicine from 1983 until 1985 in Milwaukee, WI. He went on to practice Emergency Medicine at West Allis Memorial Hospital while also working as a Physician for the Walk-in Clinic at Aurora Health in Milwaukee.

He was married to Donna K. Ritke for thirty years and together they shared two sons, Brandon Ritke Thiel, and Orin Graham Thiel.

Glenn obtained certifications for BLS, ACLS, ATLS, ACLS Instructor, ATLS Instructor Flight Physician, Flight for Life Helicopter Emergency Transport Program, Milwaukee County Regional Medical Center, and membership in A.C.E.P.

Upon his retirement in 2009, Glenn resided in Marinette County, WI., where he enjoyed his lifelong love of nature, hunting, and fishing. He took special pride in making the family’s beloved cabin into his year-round home.

He was known as an excellent cook, and loved baking fresh bread for his family. History and Greek Mythology were a passion he shared readily. An avid reader, Glenn accumulated and read many science fiction novels. His sense of humor was sharp-witted, and he loved the challenge of a good debate! An accomplished musician, Glenn could be found playing the guitar, harmonica, and whistling at any time. His music will always be in our hearts.

He is survived by the mother of his children, Donna K. Ritke; son, Orin Thiel; sister, Sandra L. Thiel; brother, Raymond B. Thiel; nieces, Shanti E. Thiel, Serena (Thiel) Hendrix, and Nalani M. Thiel; nephews, Rahman M. Thiel, and Bodhi K. Thiel; and sister-in-law, Jackie Ritke Jones.

In addition to his parents, he was preceded in death by his son, Brandon Ritke Thiel; sister, Patti J. Thiel; and nephew, Satya A. Thiel.

A private celebration of Glenn and his son, Brandon’s life, will be held with family and friends in Green Bay at a future date.

In lieu of flowers, the family requests that memorial contributions be made to: Breakthrough T1D (Type 1 Diabetes formerly JDRF, Juvenile Diabetes Research Foundation) at https://www2.breakthrought1d.org in Memory of Brandon Ritke Thiel.

Friends may leave condolences and tributes to Glenn’s family online at www.jacobsfuneralhomes.com

The family has chosen Jacobs Funeral Home-Niagara Chapel, Niagara, WI, to honor Glenn’s legacy of life.