He graduated from Longmont High School and attended college at Denver University for one year, during which time he won the western middleweight boxing title.

He failed to medal, having lost in the first round to Arthur Clifton (see Boxing at the 1924 Summer Olympics - Men's heavyweight).

Eagan became the first of six Olympians to medal in both the Winter and Summer Games,[7] followed by Jacob Tullin Thams (Norway), Christa Luding-Rothenburger (East Germany), Clara Hughes (Canada), and Lauryn Williams (United States).

Eddy Alvarez joined Eagan and Williams in 2020 as the only Americans to win medals in both the Winter and Summer Olympics.

During World War II, he served in the Air Transport Command and visited nearly every place where the Army had planes.

[4] Eddie Eagan set a world record for the fastest circumnavigation of the globe by scheduled airlines on December 13, 1948.