He was born and raised in Paris, Kentucky, served in the United States Marine Corps during World War II, and graduated from Miami University (Ohio) in 1950.
He left LSU to accept the position of athletic director at the University of Florida, a post he held from 1986 until 1992, when he returned to the professional coaching ranks as the defensive coordinator of the San Diego Chargers.
That season, the Colts reached the NFL Championship Game and remained one of the strongest teams of the 1960s, competing in Super Bowl III on January 12, 1969.
Following the Dolphins' 24–7 victory over the Minnesota Vikings in Super Bowl VIII, Arnsparger was named head coach of the New York Giants,[3][4] but managed just seven wins in his thirty-five games.
[5][6] Just two days after his dismissal from the Giants, Arnsparger was rehired by Shula and was restored to his previous position as defensive coordinator and assistant head coach.
On December 2, 1983, Arnsparger was introduced as the head football coach at Louisiana State University (LSU), though he stayed on as the Dolphins' defensive coordinator until the end of the NFL season.
His 1986 LSU squad won the school's first outright SEC title since 1970 and what would be the Tigers' last in the pre-championship game era, though the season was marred somewhat by an upset home loss to Miami University, his alma mater.
After Sports Illustrated ran a cover story about the university's issues, Arnsparger met privately with athletic director Bob Brodhead to complain that the negative coverage was harming football recruiting and to threaten to leave the school if something wasn't done.
The Florida Gators football team had been found in violation of many NCAA rules in the early 1980s and was still suffering under significant sanctions and probation when Arnsparger arrived, a situation which weakened the financial strength of the entire athletic department.
Head football coach Galen Hall was accused of committing minor rules violations, which became a major issue with the NCAA because of the just-completed probation.
[11][12] At about the same time, the NCAA was investigating allegations that the Florida Gators men's basketball program had allowed sports agents to pay star players.
[13] Sloan subsequently claimed that the allegations were false and that Arnsparger's zealous attempts to clean up Florida's athletic department turned into a "witch hunt" that unfairly punished him and his staff.
Spurrier, who had won the Heisman Trophy as Florida's quarterback in 1966, would become the school's all-time wins leader in his twelve years in Gainesville, leading the Gators to their first six conference titles and the 1996 national championship.
[16] During his time at Florida, Arnsparger was thought by some athletic department staff and boosters to be "domineering" and that, keeping with his background in coaching, he was "inflexible... sticking by his game plan at all costs.".
Just days after the team's Super Bowl appearance, Arnsparger announced his retirement, citing the prostate cancer surgery he had undergone the year before.