[1] In November 2006, Kapp was voted to the Honour Roll of the CFL's top 50 players of the league's modern era by Canadian sports network TSN.

[3] He was raised in California, in the San Fernando Valley and Salinas,[3] where he played quarterback for Hart High School in Newhall, now a part of Santa Clarita.

Kapp was named an All-American, and was also awarded the W. J. Voit Memorial Trophy in 1958 as the outstanding football player on the Pacific Coast.

[6] The Washington Redskins selected Kapp in the 18th round of the 1959 NFL draft, giving them his rights to play professional football in the United States.

[4] However, Washington never contacted him after the draft, so his only choice was to accept an offer from Jim Finks, the general manager of the Calgary Stampeders of the Canadian Football League (CFL).

[7] The following year, Kapp led Calgary to their second playoff appearance since the start of the modern era of Canadian football.

[14] To make this transaction possible, the BC Lions traded all-star defensive lineman Dick Fouts, and future Canadian Football Hall of Fame running back Bill Symons to Toronto for the CFL rights to future Canadian Football Hall of Fame wide receiver Jim Young.

Kapp, now waived from the CFL, was free to sign with the Vikings, who had previously claimed his NFL playing rights from Washington.

[18] In 1967, Kapp's first season in the NFL, he started 11 of 14 games for the Vikings, compiling an unusual record of 3 wins, 5 losses and 3 ties.

[20] Early in the 1969 season, Kapp tied an all-time record when he threw for seven touchdown passes against the defending NFL champion Colts on September 28.

[24][25] Despite Kapp being a Super Bowl quarterback, no team in the NFL made contact with him until after the start of the 1970 regular season,[26] when the Boston Patriots (1–1) signed him on October 2 to a four-year contract,[27][28][29] making him the highest paid player in the league.

The Patriots gave up defensive back John Charles and a 1972 first round draft pick (which was used to select linebacker Jeff Siemon) as compensation to the Vikings.

[4] With the top pick in the 1971 NFL draft, the Patriots selected quarterback Jim Plunkett of Stanford, the winner of the Heisman Trophy.

Kapp reported to the newly renamed New England Patriots' training camp in 1971, refused to sign a standard contract, and departed.

Programs included Ironside,[4] The Six Million Dollar Man,[38] Adam-12,[9] Emergency!,[10] Police Woman,[9] Captains and the Kings,[39] and Medical Center.

[10] Movies included Climb An Angry Mountain (1972),[39] The World's Greatest Athlete (1973),[39] The Longest Yard (1974),[38] Breakheart Pass (1975),[9] Two-Minute Warning (1976),[39] Smash-Up on Interstate 5 (1976),[39] Semi-Tough (1977),[4] The Frisco Kid (1979),[9] and Off Sides (Pigs vs. Freaks) (1984).

On Sundays, he would have his players play a game of "garbazz", described as a mix of basketball and football where the only objective is to pass the ball downfield.

Following an embarrassing 50–18 loss at Washington on October 4, Kapp expressed frustration unzipping his pants in front of the Seattle media.

The Bears responded to the student section's pre-game chants of "Win one for the zipper" by beating the Gator Bowl-bound #16 Cardinal 17–11, which gave Kapp a 3–2 record in the Big Game.

"[48] In an effort to recapture their past glory, the BC Lions of the Canadian Football League (CFL) hired Kapp as the team's new general manager in 1990.

Kapp was fired eleven games into the Lions' schedule; his most valuable legacy was the signing of quarterback Doug Flutie, who would blossom into a star in the CFL during the 1990s.

He was one of the owners of Kapp's Pizza Bar & Grill in Mountain View, California, which contained memorabilia from his career and closed in 2015.

[54] In 2015, grandson Frank Kapp continued the Cal football tradition as a freshman tight end with the Golden Bears.