Jack Avon Harbaugh^[1] (born June 28, 1939) is an American football coach and former player. He served as the head football coach at Western Michigan University from 1982 to 1986 and Western Kentucky University from 1989 to 2002, compiling a career college football head coaching record of 116–95–3. In his final year at Western Kentucky, he led the 2002 Hilltoppers to an NCAA Division I-AA Football Championship title. In 2023, Harbaugh came out of retirement to become assistant head coach of the Michigan Wolverines under his son Jim (who was head coach at the time) and helped lead the team to win the 2024 College Football Playoff National Championship.^[2]

Harbaugh's sons, John and Jim, are the first pair of brothers to serve as head coaches in the NFL and the first pair of head coaching brothers to face off in a Super Bowl.

Harbaugh was born in Crestline, Ohio, to Marie Evelyn (née Fisher) and William Avon Harbaugh. He is of German and Irish descent.^[1] He graduated from Crestline High School in 1957. At Crestline, he was a four-year letterman in both football and baseball. He was an all-state quarterback and shortstop in his senior year. He was also a two-time letterman in basketball.^[3]

He played college football for the Bowling Green State University Falcons from 1957 to 1960, where he was a three-time letterman. In his junior year, the Falcons finished the season 9–0 and were named the small college division national champions.^[4][5] He was drafted in the 1961 AFL draft by the Buffalo Bills as a running back.^[3][6]

Harbaugh began as an assistant coach to Jerry Nowak at Perrysburg High School in Perrysburg, Ohio, southwest of Toledo. Both sons were born while Harbaugh was in Perrysburg. In 1964, Harbaugh was the head coach of Eaton High School football team in Eaton, Ohio. His record was 5–4–1, their first winning season in many years. In 1965 the team went 6–4. In 1966, Harbaugh was the head coach of the Xenia High School football team in Xenia, Ohio. His record for the one year that he coached was 8–1–1.^[7] He received championship honors in the Western Ohio League and was named conference Coach of the Year.^[8]

Harbaugh served as an assistant in various college programs from 1968 to 1981.

From 1982 to 1986, he served as the head football coach at Western Michigan University and compiled a 25–27–3 record. From 1989 to 2002, he was the head football coach at Western Kentucky University. During his tenure with the Hilltoppers he posted a 91–68 record, including three 10-win seasons. The Hilltoppers were the only team to rank in the top 10 every year in rushing offense from 1991-2002.^[3] In 2002, the WKU squad won the NCAA Division I-AA national football championship.

After leaving Western Kentucky, Harbaugh served as an associate athletic director at Marquette University, Milwaukee, Wisconsin, where his son-in-law, Tom Crean, was the head coach of the men's basketball team. Harbaugh has also served as an assistant coach at Morehead State University, Bowling Green State University, the University of Iowa, the University of Michigan, Stanford University, the University of Pittsburgh, and the University of San Diego.

Harbaugh retired in 2006, but served as Stanford's running backs coach in the 2009 Sun Bowl under his son, Jim. Jack filled in for Willie Taggart, who had recently been hired as the new head football coach at WKU.

Following his son Jim's three-game suspension in 2023, Harbaugh unretired to serve as an assistant head coach for Michigan, and would wind up winning the 2024 College Football Playoff National Championship alongside his son.^[9]

Harbaugh married his wife, Jacqueline M. "Jackie" Cipiti, in 1961. They have three children: John, Jim, and Joani. Jack and Jackie settled in Mequon, Wisconsin, when he took the position as Associate Athletic Director for Marquette University in Milwaukee.^[10] Harbaugh is a member of the Bowling Green State University chapter of Phi Delta Theta Fraternity.

Their two sons, Baltimore Ravens head coach John Harbaugh and Los Angeles Chargers head coach Jim Harbaugh, were the first pair of brothers to serve as head coaches in the National Football League (NFL).^[11] The brothers coached their teams in a game unofficially nicknamed the 'Harbaugh Bowl' and 'Har-bowl' on Thanksgiving Day 2011—one day before Jack and Jackie's fiftieth wedding anniversary—in which John's Ravens beat Jim's 49ers, 16–6. They faced each other again in a second 'Har-bowl' when Baltimore beat San Francisco on February 3, 2013, at Super Bowl XLVII in New Orleans by a score of 34–31.^[12] Jim also played as quarterback at Michigan and for 15 seasons in the NFL for six different teams from 1987 to 2001 before entering coaching.

Their daughter Joani's husband, Tom Crean, has been the head men's basketball coach at Marquette, Indiana, and Georgia. They met while Jack was the head football coach at Western Kentucky University and Crean was an assistant basketball coach to Ralph Willard.