Kingsford – Kenneth "Ken" F. Ullenius, 88, of Kingsford, Mich., passed away on Sunday, November 2, 2025, at UP Health Systems – Marquette, Mich.

Born on May 30, 1937, in Chicago, Ill., Ken was the son of the late Folke Ullenius and Lilly (Ohlberg) Thorvaldsen. He graduated from the University of Illinois in 1960 with a degree in mechanical engineering and went on to enjoy a long and successful career in the field. Over the years, he contributed his expertise to several companies, including Chicago Aerial Industries in Barrington, Ill.; Kaydon Corporation in Muskegon, Mich.; Bally Life Fitness in Rosemont, Ill.; and Zebra Technologies in Vernon Hills, Ill. His inventive mind earned him recognition on 4 patents.

A natural athlete, Ken excelled in many sports — particularly bowling, baseball, softball, darts and golf. In retirement, he could often be found fishing on the Menomonee River, flipping between televised sporting events, chain sawing and splitting wood, enjoying his daily naps, or tinkering in his workshop — typically with his trademark cigar perched on his lips.

Ken, known to his family and friends as "Popsy," is survived by his loving wife of 64 years, Janet Ullenius; their children, Deborah (Brian) Devroy, Daniel Ullenius, and Steven (Lisa) Ullenius, MD; his sister, Linda (Jerry) Honda; five grandchildren; two step grandchildren; and four step great grandchildren.

In addition to his parents, Ken was preceded in death by his brother, Tom Ullenius; and his sister and brother-in-law, Betty J. (Allen) Tuthill.

A Celebration of Ken's Life will be held in the spring.

Friends may share condolences and tributes with Ken's family online at www.jacobsfuneralhomes.com.

The family has entrusted Jacobs Funeral Home and Cremation Services, Iron Mountain, Mich., to honor Ken's life and legacy.