Knap also worked as a high school teacher and coach, and served in the United States Navy during World War II.

The oldest son of Polish immigrants, Knap was born and raised in Milwaukee, Wisconsin, and graduated from Riverside High School (a.k.a.

Knap was also a pitcher and utility player for three seasons on the varsity baseball team,[20][21][22] and a member of the Sigma Alpha Epsilon fraternity.

[23][24] After earning a bachelor's degree in education in 1939,[23] Knap became a high school teacher and coach for three years in Bonners Ferry,[25][26][27] just south of Canada.

While waiting for his military commission following the outbreak of World War II, he spent a fall at Lewiston High School in 1942 as an assistant under former Vandal teammate Steve Belko.

[28][29] Knap served in the U.S. Navy, then returned to coaching after the war back in Idaho at Potlatch, near Moscow, and stayed with the Loggers until the summer of 1949.

With mixed support from his administrators, Knap resigned in January 1967 to accept a position with the BC Lions in the Canadian Football League (CFL).

Knap led the Broncos to a 71–19–1 (.786) record in eight years, including three ten-win seasons and three consecutive Big Sky titles (1973–75).

Knap married Doris Adella "Mickey" McFarland (1920–2013), a former UI student born in St. Maries,[43][44] during his first year as a teacher.