"Mississippi Mud" is a 1927 song written by Harry Barris and James Cavanaugh, first made popular by Bing Crosby as a member of The Rhythm Boys, who recorded the song on June 20, 1927 for Victor. It was recorded by Paul Whiteman's orchestra in 1928 with vocals by Irene Taylor and The Rhythm Boys featuring Bing Crosby and with Bix Beiderbecke on cornet. Two takes were released on Victor. Later it was also sung briefly by the Rhythm Boys in the 1930 film King of Jazz. The song was sung too in the 1931 Toby the Pup cartoon Down South.
The song has been recorded by a number of artists since, including Frankie Trumbauer and His Orchestra with Bix Beiderbecke, Dean Martin, and Ray Charles, and become one of the standards of the American songbook, but with lyrics revised from the original politically incorrect version. The original lyrics featured the refrain line: "When the darkies beat their feet on the Mississippi Mud." which has since been revised to: "When the people beat their feet on the Mississippi Mud."
The song was featured in the M*A*S*H episode "The General Flipped at Dawn", being sung and danced to by Harry Morgan (playing Brigadier General Steele, not Colonel Potter as he would go on to portray later in the series) after he asks an African American helicopter pilot to do a song number.