Around 1928, in Kansas City, Keg and Budd played in several bands but by 1930 Keg left for Chicago to play with Louis Armstrong, recording his first solo on Armstrong's Basin Street Blues album. When in 1933 Keg went to New York, he played with such greats as Fletcher Henderson and Benny Carter, eventually playing with Cab Calloway at the Cotton Club. Keg remained with Cab Calloway for some 15 years, coinciding with fellow trombonists Claude Jones and DePriest Wheeler and later Tyree Glenn and Quentin Jackson, as well as other musicians such as Dizzy Gillespie, before moving to Los Angeles where he briefly changed careers renovating houses. During the 1950s he returned to New York where he and his brother recorded the album Let's Swing. In 1961, Keg began playing with Ray Charles and was still in his band when Keg died in Chicago on 8 November 1967.
His son, Frederic Homer Johnson, also called "Keg", is a record producer whose first production was the R&B oldies hit, "You Got Me Going In Circles". He also produced The Sylvers, Lakeside[disambiguation needed], Shalamar, Levert, The Brothers Johnson, Gene Harris, Bobby Womack, The Blind Boys of Alabama, and more.