Cal

Football was first played on the Cal Poly campus in 1916. At that time, Cal Poly was a vocational school, as it did not become a four-year college until 1941.

1915 to 1940s: The beginning

The California Polytechnic School played mostly high school teams and college freshmen teams for its first 16 seasons. In 1933, the Mustangs enjoyed their first undefeated season under coach Howie O'Daniels. During the 1933 campaign, the Mustangs did not allow a single point during that season. Cal Poly officially became a four-year school in 1941 and posted a 5–3–1 record under O'Daniels. Football was put on hold during World War II ('43 and '44) and resumed in 1945.

1950s: Jeter, Madden, Beathard leave legacy

Under coach LeRoy Hughes, Cal Poly experienced its second undefeated season in 1953. In the decade of the 1950s, the Mustangs posted a record of 67–29–1. During this time, All-American Stan Sheriff became Cal Poly's first player to join an NFL roster, beginning with the Pittsburgh Steelers in 1954.

Hughes' teams also included future Chicago Bears running back Perry Jeter and future Pro Football Hall of Fame inductee John Madden, who was known as a bruising tackle. Upon graduation, Madden was drafted by the Philadelphia Eagles.

Of Jeter, legendary Bears founder George Halas commented in 1954: "Never have we received a more accurate appraisal (in promotional assessment) of a player than LeRoy Hughes gave us on Jeter." Joining Madden and Jeter on the Mustang roster was quarterback and defensive back Bobby Beathard, who would be inducted into the Pro Football Hall of Fame in 2018 as the architect and general manager responsible for building the Washington franchise into a perennial Super Bowl-winning and contending dynasty.

1960s: Tragedy strikes Cal Poly; Harper brought on

Tragedy struck in 1960 following a game at Bowling Green State University on Saturday, October 29, 1960, when a plane leaving Toledo Airport crashed, killing 22 people. This included 16 Mustang football players and the team manager. The next seven seasons produced a 22–45 record. Joe Harper, then a Colorado assistant, was hired as Mustang head coach on February 7, 1968. Harper, a former offensive guard for UCLA (1956–58), directed Cal Poly to 7–3 and 6–4 seasons to end the decade, respectively. In the final year of the decade, Cal Poly upset Fresno State 21–17, leading the Mustang Daily campus newspaper to publish a rare all-capped double-truck headline declaring the game as "One of the Greatest Wins in Poly Grid History". At the time, Harper told the Fresno Bee the win was "the greatest game I have ever been involved with." The result also made the sports section of the San Francisco Chronicle, which noted the Mustangs' first win over the Bulldogs in 12 years.

1970s: Harper builds a dynasty

Under Harper, Cal Poly produced an 8–0–1 regular-season record in 1972 and received a trip to the Camellia Bowl to play in the Western Regional Championship Game of the NCAA's College Division. Cal Poly was ranked No. 3 in the division by both the AP and UPI polls heading into the postseason. They would end up losing 38–21 to the University of North Dakota (North Central Conference co-champs) in the bowl game hosted in Sacramento's Hughes Stadium, telecast regionally on ABC. In 1978, the Mustangs would make it to the NCAA Division II playoffs but lost to Winston-Salem State.

Another highlight during the decade was Cal Poly's most recent football victory over Fresno State, which came 26–0 on Oct. 6, 1979. The score marked, at the time, the first shutout in the 57-year history between the two programs. Mustang safety Chris Jones had two interceptions in the game, while fullback Paul Dickens led the offense by rushing for 163 yards on 35 carries.

Each of the ten Mustang football teams in the 1970s posted a winning season.

1980s: Mustangs win national title

In 1980, Harper led the Mustangs to the NCAA Division II National Football Championship. Cal Poly defeated Eastern Illinois in the championship game on ABC and would finish the season with a 10–3 record that included a win over eventual-Division I-AA national champion Boise State. Never before or since has a D-II team defeated the eventual I-AA national champion and won a D-II national title in the same year.

During the 1980 season, running back Louis Jackson led the nation at the Division II level with 1,424 rushing yards on 287 carries.

Robbie Martin, who starred in the NCAA championship win, compiled a career punt-return average of 16.9 yards per runback, graduating after the 1980 title season with the third-best PR average in division history at the time.

Following the national title, the Mustangs were honored with a parade through downtown San Luis Obispo on December 15, 1980. The parade traveled down Higuera Street before a rally held in Mission Plaza. Then-mayor Lynn Cooper spoke at the celebration.

On November 20, 1982, Cal Poly's Clarence Martin set an all-time Division II single-game record for most yards per kickoff return (minimum of three returns), averaging 71.7 yards (215 total) on his three KRs vs. then-rival Pomona. The record was finally broken after 39 years by Carson-Newman return specialist DeQuan Dudley in 2021.

1990s: The move to Division I

In 1990, coach Lyle Setencich would lead the Mustangs to another playoff appearance before losing in the second round to powerhouse North Dakota State. The 1990 Mustangs yielded just 11.3 points per game, the best defensive average throughout Division II for the year. The defensive front was led by lineman Pat Moore, who received an invitation to the NFL Scouting Combine after compiling 67 tackles and 9.5 sacks during the 1990 season. Also aiding the defense was punter Doug O'Neill, who in 1991 led the nation in punting average, with 45.1 yards per punt, while earning first-team All-American honors from the AP.

In 1994, Cal Poly would make the jump to Division I-AA (now Football Championship Subdivision) with head coach Andre Patterson at the helm. The Mustangs would see moderate success, posting a 7–4 record in Patterson's first year followed by two 5–6 seasons before Patterson departed for a position as an NFL line coach.

In 1997, Larry Welsh took over the program and led the Mustangs to a 10–1 record and a national ranking of 18th. The season was highlighted by a 38–35 win at FBS-level New Mexico State. However, still only in its fourth year in the I-AA ranks at the time, Cal Poly was not extended an invitation to the national playoffs. Welsh (a 2017 inductee to the CIF Southern Section Hall of Fame) would follow that season with three 3–8 seasons and was not contractually renewed by then-athletic director John McCutcheon. The 1997 team's omission from the postseason was referred to as a "snub" by the Los Angeles Times following the regular season.