This is the sixth in a series of articles on the history of Princeton football in honor of its 135th anniversary.
In the fall of 1950 the American economy was booming, A&W Root Beer Co. was founded, the Soviets had become a nuclear power, Disney's Cinderella had just opened, the Korean War had begun and, for the first time in decades, Princeton football looked to have a very promising season.
Under the charismatic leadership of newly hired head coach Charlie Caldwell '25, the Tigers entered the 1950 season coming off two winning seasons and the first three Big Three wins since 1939. This, combined with the fact that the program was returning 12 starters, gave the team hope for the upcoming year.
"We had played together for a few seasons by 1950," Billy "Mighty Mouse" Kleinsasser '51 reminisced. "We expected success. The ability level was high; we were all good students, and we had excellent coaching."
Yet, as confident and ambitious as they were, no one, players and coaches alike, expected that the 1949 end-of-season loss to Cornell would be the last Tiger loss until 1952 — a span of 24 games — and that the next two years would include Lambert Trophies, national rankings, All-American nominations and a Heisman Trophy winner.
Caldwell, who had come back to his alma mater in 1945 after coaching at Williams, had turned the post-World War II Princeton football program around in two short years under his unique — and often criticized — single wing offensive formation. While most other programs were converting to the "T" formation, Caldwell stuck with his old-school playbook, convinced that its emphasis on strength, conditioning and teamwork was the combination that would propel the Tigers to success.
And it did. The accented teamwork aspects of the program played to Princeton's strength. With only six seniors out of 22 starters, the Tiger squad boasted impressive depth and an extremely strong junior class, including several All-Americans and a future Heisman winner, Dick "Kaz" Kazmaier '52.
In his three years on varsity, Kazmaier played a total of 27 games and accumulated 35 passing touchdowns and 20 rushing touchdowns. Over his career he averaged 5.3 yards per carry and a .619 completion percentage on passing. In 1950 Kazmaier was second in the nation in total offensive yards and was a major contributor to Princeton's perfect 9-0 record.
Though a Heisman Trophy would not come until the following season, completing that 1950 season with a perfect 9-0 record seemed almost too easy at times for the Tigers. In those nine games, they averaged nearly 40 points per contest, and their largest margin of victory was 69 points (against Williams). They averaged 433.7 yards per game, while the opposition averaged a mere 70 yards per game.
With several players who could play multiple positions and contribute on all levels, the team dynamic was what took the Tigers from good to great and helped them post such incredible statistical discrepancies.
"The accolades were more than any of us expected, I think, and it was a good feeling to contribute in that way," Kleinsasser said. "There was a special chemistry on that team that made it all possible. I live very far away, and the alumni reports just don't match the spirit of that championship year."
Expected or not, the accolades certainly did come rolling in, as the Associated Press named Caldwell Coach of the Year and ranked Princeton sixth in the nation. After a 27-0 win over Cornell, an Ivy favorite going into the season, the Tigers received the prestigious Lambert Trophy, stripping Army of their Eastern Championship title of the last six years.

But the historic team of 1950 did not play the sport for the fame; these played it for each other and for their coach. Though faced with challenges throughout the season, their joint dedication proved time and again to be what drove their ultimate success.
"My most memorable game of the season was the last game against Dartmouth played in hurricane winds and rain," said Kazmaier, who earned All-American honors in 1950 with teammates Reddy Finney '51 and Holly Donan '51. "That we were able to win under those conditions was a testament to the strength and purpose of the team."
The undefeated 1950 season stands out in Princeton's rich history as a defining point for Tiger sports for the group of incredible individuals who were all at the right place at the right time. Though the Caldwell days are long gone, those associated with Princeton, both past and present, continue to honor those glory days of Tiger football.
"An undefeated season is both rare and indelible," Kazmaier said. "And though specific incidents may be hard to recall, the lasting impression of those great men and players will always remain."