Crosby began singing in the early 1930s with the Rhythm Boys, which included vocalist Ray Hendricks and guitarist Bill Pollard, and with Anson Weeks (1931–34) and the Dorsey Brothers (1934–35).
He led his first band in 1935 when the former members of Ben Pollack's band elected him their titular leader.
In 1935 he recorded with the Clark Randall Orchestra led by Gil Rodin and featuring singer Frank Tennille (a.k.a.
Clark Randal), father of Toni of Captain and Tennille.
Glenn Miller was a member of that orchestra, which recorded the Glenn Miller novelty composition "When Icky Morgan Plays the Organ" in 1935.
Crosby's "band-within-the-band," the Bob-Cats, was a dixieland octet with soloists from the larger orchestra, many from New Orleans.
The band included at various times Ray Bauduc, Yank Lawson, Billy Butterfield, Charlie Spivak, Muggsy Spanier, Irving Fazola, Nappy Lamare, Jack Sperling, Joe Sullivan, Jess Stacy, Bob Haggart, Walt Yoder, and Bob Zurke.

In the spring of 1940, during a performance in Chicago, teenager Doris Day was hired as the band's vocalist.

For its theme song, the band chose George Gershwin's song "Summertime."
The band's hits included "South Rampart Street Parade", "March of the Bob Cats", "In a Little Gypsy Tea Room", "Whispers in the Dark", "Day In, Day Out", "Down Argentine Way", "You Must Have Been a Beautiful Baby", "Dolores", and "New San Antonio Rose" .
A bass-and-drums duet between Haggart and Bauduc, "Big Noise from Winnetka", became a hit in 1938–39.

There were reunions in the 1950s and 1960s.
Bob Haggart and Yank Lawson organized a band that combined dixieland and swing to try to carry on the legacy of Bob Crosby.
From the late 1960s until the mid 1970s, the band was known as the World's Greatest Jazz Band, but when both became dissatisfied with the name they changed it to the Lawson-Haggart Jazz Band.
Crosby began singing in the early 1930s with the Rhythm Boys, which included vocalist Ray Hendricks and guitarist Bill Pollard, and with Anson Weeks (1931–34) and the Dorsey Brothers (1934–35). He led his first band in 1935 when the former members of Ben Pollack's band elected him their titular leader. In 1935 he recorded with the Clark Randall Orchestra led by Gil Rodin and featuring singer Frank Tennille (a.k.a. Clark Randal), father of Toni of Captain and Tennille. Glenn Miller was a member of that orchestra, which recorded the Glenn Miller novelty composition "When Icky Morgan Plays the Organ" in 1935. Crosby's "band-within-the-band," the Bob-Cats, was a dixieland octet with soloists from the larger orchestra, many from New Orleans. The band included at various times Ray Bauduc, Yank Lawson, Billy Butterfield, Charlie Spivak, Muggsy Spanier, Irving Fazola, Nappy Lamare, Jack Sperling, Joe Sullivan, Jess Stacy, Bob Haggart, Walt Yoder, and Bob Zurke.
In the spring of 1940, during a performance in Chicago, teenager Doris Day was hired as the band's vocalist.
For its theme song, the band chose George Gershwin's song "Summertime." The band's hits included "South Rampart Street Parade", "March of the Bob Cats", "In a Little Gypsy Tea Room", "Whispers in the Dark", "Day In, Day Out", "Down Argentine Way", "You Must Have Been a Beautiful Baby", "Dolores", and "New San Antonio Rose" . A bass-and-drums duet between Haggart and Bauduc, "Big Noise from Winnetka", became a hit in 1938–39.
There were reunions in the 1950s and 1960s. Bob Haggart and Yank Lawson organized a band that combined dixieland and swing to try to carry on the legacy of Bob Crosby. From the late 1960s until the mid 1970s, the band was known as the World's Greatest Jazz Band, but when both became dissatisfied with the name they changed it to the Lawson-Haggart Jazz Band.
Bob Crosby