He played and coached both collegiately for Harvard University and professionally in the National Football League (NFL).

His brother Ralph Horween was also an All-American football player for Harvard, and also played and coached in the NFL for the Cardinals.

Horween's parents, Isidore and Rose (Rabinoff), immigrated to Chicago from Ukraine in the Russian Empire in 1892.

[13] In his freshman year, he played both football (as a fullback) and baseball (as a pitcher), and was a member of the track team as a shotputter.

[12][21] In 1919, Donald Grant Herring ranked him the Second-team fullback on the Princeton-Yale-Harvard composite team.

[25] The New York Times wrote: "The way he smashed through the line was considerable... there were even some protests that this dark-haired, sturdily built Crimson fullback was a little too rough.

"[21] In 1920 he was chosen Walter Camp third-team All-American and selected by a number of newspapers to the All-America first-team.

[28] On November 12, 1922, he made a long pass to Paddy Driscoll for the game's only touchdown, in a 7–0 victory over the Akron Pros.

[29] On December 2, 1923, he kicked a 35-yard (32 m) field goal and his brother ran for a touchdown as the Cardinals beat the Oorang Indians, 22–19.

Horween returned to Harvard as the school's head football coach from 1925 to 1930, compiling a record of 21–17–3.

He recalled that anti-Semitic posters aimed at Coach Horween were displayed at a game in Ann Arbor, Michigan.

The couple had a long engagement, as they had agreed to postpone the wedding until the Harvard football team defeated Yale.