John Edgar “Jack” Seitz was mayor of Des Plaines for eight years in the 1980s and before that had served for 14 years as an alderman in the northwest suburb.

Seitz also taught business and marketing classes at Oakton Community College in Des Plaines — now known as Oakton College — for more than two decades.

“He was a phenomenal leader,” said retired Oakton professor George Heyman, who shared an office with Seitz at the college. “One of his innovations was becoming a part-time mayor of Des Plaines instead of the position being full-time. He was very politically astute and very caring of people.”

Seitz, 92, died of natural causes on July 10 at his home, his daughter Janet said. A Des Plaines resident, he had been battling many health challenges, she said.

Born in Detroit, Seitz came to the Chicago area for college, and he earned a bachelor’s degree in journalism from Northwestern University’s Medill School of Journalism in 1952. He then served in the U.S. Marine Corps in Korea, rising to the level of lieutenant colonel.

After his active duty concluded, Seitz returned to the Chicago area and began working for the National Safety Council in 1955 as a statistician. The next year, he shifted gears to work for Continental Casualty Co. as a copywriter and account supervisor, and then in 1958 he joined Chicago-based Encyclopaedia Britannica as a contest and awards manager.

While working, Seitz earned an MBA from Northwestern University in 1960. He left Encyclopaedia Britannica in 1964 to join United Airlines in the firm’s advertising and promotion department, and he rose to become assistant to the director of promotion before leaving United in 1971.

Seitz decided to change careers that year, when he began teaching business and marketing classes at Oakton.

Seitz and his wife, Marilyn, settled on living in Des Plaines after a friend from his Marine Corps Reserve unit had purchased a new house there. They liked the area so much that they bought the lot next door and built their own home in 1962, he told the Tribune in 1986.

Seitz soon became involved in a civic group that was fighting a local rezoning proposal before the Des Plaines City Council. That led to a role as a GOP precinct captain, and then in 1967, Seitz ran for and won a seat as alderman.

Seitz was reelected in 1971, 1975 and 1979. As an alderman, he chaired the city’s Fire Committee, and in 1973, he convinced his colleagues to set aside funds to implement a paramedic program to be run by the Des Plaines Fire Department, with firefighters trained to be paramedics. In late 1974, the department placed its first mobile intensive care unit in service.

Seitz won election as mayor in 1981.

“I felt things weren’t moving fast enough,” Seitz told the Tribune in 1986. “I wanted redevelopment to proceed at a faster price than I perceived it was happening.”

Seitz’s campaign included a pledge he soon implemented to return the position of mayor from a $32,500-a-year full-time position to a $9,600-a-year part-time post.

“One of my continuing goals in this office is to improve the efficiency of government,” he told the Tribune. “I know that’s a general statement, but there always are little things you can find to make it run better.”

Other issues Seitz grappled with during his two terms as mayor included the redevelopment and revitalization of Des Plaines’ central business district. He founded the Des Plaines Economic Development Commission in 1982, and he oversaw a variety of work, including the construction of a new train station and plans for a $34 million residential and commercial development nearby.

Seitz also was a forceful advocate for his community in battling with the city of Chicago over noise and air quality from nearby O’Hare International Airport. And he was a major promoter of Des Plaines as an economic engine in its own right, with a daytime population of almost 100,000 that was driven by office and light manufacturing workers.

“I’m tired of the attitude that we’re a ‘suburb’ of Chicago,” he told the Tribune in 1986. “We don’t have to depend on someone else to keep going.”

Seitz and the village administration also dealt with two major floods that caused problems in Des Plaines in 1986 and 1987. In addition, he served as president of the Northwest Municipal Conference, a consortium of northwest suburbs, from 1988 until 1989.

Seitz lost reelection in 1989, but voters also defeated his opponent’s pet campaign plank — a referendum proposal to convert Des Plaines to a form of government in which the post of mayor is a full-time job, with the power to hire and fire department heads.

After retiring from Oakton in 1992, Seitz spent considerable time traveling, including to all 50 states and to the Arctic Circle. He also traveled to Europe and Asia.

In addition to his daughter, Seitz is survived by his wife of more than 65 years, Marilyn; three other daughters, Laura Seitz-Peirson, Mary Seitz-Pagano and Jeanine Seitz Sappenfield; three sons, John, Paul and Ed; 19 grandchildren; three step-grandchildren; and six great-grandchildren.

Services were held.

Goldsborough is a freelance reporter.

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