KSO, located at 1370 AM, moved from Clarinda, Iowa into Des Moines in 1932. On March 17, 1935, the station officially became KRNT and moved to 1320 AM (KWCR moved from Cedar Rapids, Iowa that same year and adopted the KSO call sign, also effective March 17, 1935). At that time, both stations were owned and operated by subsidiary corporations of the Des Moines Register-Tribune. KRNT moved to the current 1350 AM frequency in 1941.
Then-owners Cowles Media started up a sister station, KRNT-FM (104.5) in 1948, but took it off the air and returned the license in 1955, the same year they started up KRNT-TV (Ch. 8). In 1970, they signed on another KRNT-FM (102.5 FM).