John von Holdt was born on August 14, 1919 in Chicago. He attended Senn High School where he became "All-Around Gymnastics City Champion". After graduation, in 1937, he began his lifelong career in the Tool and Die and Moldmaking industry by apprenticing in various Chicago area machine shops. He also completed the Plastics engineering Program at northwestern University Technological Institute.

In September 1944, he was inducted into the United States Army and was assigned to the Pacific Theater during World War II. He served as a Lieutenant in the Army Corps of Engineers in the Phillipine Islands and in Korea.

In 1950 he founded Plas-Tol Co. of Niles, Illinois and built it into one of the finest specialty moldmaking companies in the U.S. with mold exports to Europe, North and South America and the Far East.

He was recognized as one of the most inventive and creative moldmakers, having received over 55 United Stated patents and hundreds of corresponding foreign patents in the fields of mold and plastic product design. From 1969 - 1971 he served as National Chairman of the Moldmaker's Division of the society of the Plastics Industry and was much sought after keynote speaker at many of the technical and business conferences in the plastics industry. Mr von Holdt was the only three-time winner of the prestigious "Bachner Award" for plastic product design. In 1990 he was presented with the Society of Plastics Engineers "Mold Maker of the Year award". The following year he was unanimously nominated by his peers to receive the moldmaking "Industry Achievement Award" which was presented to him at the tri-annual banquet by The Plastics Academy.

His wife, Pauline, daughter, Janice Anderson , son John Jr., granddaughter Christine Newton, and grandsons Alexander von Holdt survive him.