KANSAS CITY, Mo. (AP) -- Gunther Cunningham's life would have been vastly different had his family not emigrated from postwar Germany, settling in California when he was a young boy.
For one thing, he almost certainly never would have dedicated his life to football.
Yet Cunningham would go on to spend more than five decades in the game, including coaching stints in college and the CFL before making a name for himself in the NFL. He worked for six different franchises over 34 years in the league, including a two-year stint as head coach of the Kansas City Chiefs.
Cunningham died on Saturday after a brief illness. He was 72.
His wife, Rene, said in a statement Monday that Cunningham died in Detroit, where he had served as defensive coordinator and a senior coaching assistant for the Lions before retiring in 2016.
"My family and I are deeply saddened to hear the news of Gunther's passing," Chiefs owner Clark Hunt said in a statement. "He led some of the most feared defenses in our franchise's history with his energetic and motivating coaching style. Gunther made a tremendous impact on so many lives on and off the playing field in nearly five decades of coaching."
The Lions said in a statement that Cunningham will "forever be remembered as one of the great men in our game. He left a lasting impact on every person who was fortunate enough to work with him."
Cunningham's father, Garner, was an American serving in the Air Force in Germany when he met his German wife, Katherina. Their precocious boy was born in Munich in 1946, and the family soon moved to the U.S. and settled in California, where Cunningham -- who spoke no English -- was ridiculed like many post-World War II immigrants for both his accent and ancestry.
It was on the football field where he found his voice.
Cunningham became a star linebacker for his high school team in Lompoc, and earned a scholarship to play at Oregon. His aptitude for the game made him a natural coach, and Cunningham got his start as the Ducks' defensive line coach from 1969-71.
He later coached at Arkansas, Stanford and California before a stint with Hamilton in the CFL. He then followed Frank Kush to the Baltimore Colts, where he got his first NFL coaching job.
Colts owner Jim Irsay tweeted that Cunningham was "one of the finest men in our business."
Cunningham eventually became one of the most aggressive and successful defensive coaches in the league, burnishing his reputation with the Chargers and Raiders before landing in Kansas City. He was an integral part of Marty Schottenheimer's best teams as the Chiefs' defensive coordinator, and was promoted to head coach when Schottenheimer resigned after the 1998 season.
He went 9-7 in his first year and 7-9 in his second, and his only head coaching stint ended on a sour note. Cunningham claimed he was never told by management that he'd been fired, learning it instead from reporters when he arrived to work in the morning.
Cunningham spent some time with the Titans before Dick Vermeil lured him back to the Chiefs as his defensive coordinator. He spent the rest of his career with the Lions.
"I had the honor to coach with him & against him," tweeted longtime coach Jeff Fisher, who had Cunningham on his staff in Tennessee. "You'll never meet another man with such a passion for people, family and football. We will miss him deeply."
Cunningham was known for his fiery demeanor and colorful vocabulary -- yes, he picked up English, but his players would joke that he also knew plenty of French. Even in his final years on the sideline in Detroit, it wasn't uncommon to see Cunningham drop-kicking a clipboard in frustration.
But he also was the consummate players' coach, putting their best interests first.
"So sad to hear of the passing of one of the best coaches in the game," said Rich Gannon, who was quarterback in Kansas City during the late 1990s. "I went against him and his defense in practice every day for four years with the Kansas City Chiefs and it definitely made me a better player."
Cunningham is survived by Rene, his wife of nearly 50 years, and their son Adam and daughter Natalie. The family is planning a memorial service at a later date.