Ralph D. "Slouie" Chapman (May 8, 1892 – August 1969[1]) was an American football player.

[2] He played at the guard position for Robert Zuppke's University of Illinois football team from 1912 to 1914.

Chapman was selected as the captain of the 1914 Illinois football team and a first-team All-American at the guard position in 1914.

When the United States entered World War I in 1917, he applied for and was accepted into the officers' training program at Fort Sheridan.

He was commissioned a first lieutenant was among the first contingent of reserve officers training camp graduates to be sent to France.