Bob Crosby (August 23, 1913 Spokane, Washington – March 9, 1993 La Jolla, California) was an American dixieland bandleader and vocalist, best known for his group Crosby and the Bob-Cats.

He was the youngest of seven children: five boys, Larry (1895-1975), Everett (1896-1966), Ted (1900-1973), Harry (1903-1977, popularly known as Bing Crosby) and Bob; and two girls, Catherine (1905-1988) and Mary Rose (1907-1990). His parents were English-American bookkeeper Harry Lowe Crosby (1871-1950) and Irish-American Catherine Harrigan (1873-1964), (affectionately known as Kate), the daughter of a builder from County Mayo in Ireland. His paternal ancestors Thomas Prence and Patience Brewster were born in England and immigrated to the U.S. in the 17th century; Brewster's family came over on the Mayflower.

Bob Crosby began singing 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 as titular leader. His most famous band, the Bob-Cats, was a Dixieland jazz group with members from the Bob Crosby Orchestra. Both the Bob Crosby Orchestra and the smaller Bob-Cats group specialized in Dixieland jazz, presaging the traditional jazz revival of the 1940s. Crosby's singing voice was remarkably similar to that of his brother Bing, but without its range.

The Bob Crosby Orchestra and the Bob Cats included (at various times) Yank Lawson, Billy Butterfield, Muggsy Spanier, Matty Matlock, Irving Fazola, Ward Silloway, Warren Smith, Eddie Miller, Joe Sullivan, Bob Zurke, Jess Stacy, Nappy Lamare, Bob Haggart, Walt Yoder, Jack Sperling, and Ray Bauduc.

Hits included "Summertime" (theme song), "In a Little Gypsy Tea Room," "Whispers in The Dark," "South Rampart Street Parade," "March of the Bob Cats," "Day In, Day Out," "You Must Have Been a Beautiful Baby," "Dolores" and "New San Antonio Rose" (last three with Bing Crosby). A remarkable bass and drums duet between Haggart and Bauduc, "Big Noise From Winnetka," became a hit in 1938-39.

Two of his songs were included in the successful 2008 RPG video game Fallout 3. The tracks "Way Back Home" and "Happy Times" (from the 1949 Danny Kaye film "The Inspector General") appeared on an in-game radio feature. "Way Back Home" also appeared on promotional cds offered for the game through Gamestop.

Radio
During World War II, Bob spent 18 months in the Marines, touring with bands in the Pacific. His radio variety series, The Bob Crosby Show, aired on NBC and CBS in different runs between the years 1943 to 1950, followed by Club Fifteen on CBS from 1947 through 1953 and a half-hour CBS daytime series, The Bob Crosby Show (1953-1957).

On September 14, 1952, Bob replaced Phil Harris as the bandleader on The Jack Benny Program, remaining until Benny retired the radio show in 1955 after 23 years. In joining the show, Bob became the leader of the same group of musicians who had played under Harris. According to Benny writer Milt Josefsberg, the issue was budget. Because radio had strong competition from TV, the program budget had to be reduced, so Bob replaced Phil. Prior to joining Benny on the radio, Crosby, who was based on the East Coast, would often play with Benny during Benny's live New York appearances, and he was seen frequently throughout the 1950s on Benny's television series.

As a performer, Crosby had tremendous charisma and wit combined with a laid back persona. He was able to swap jokes competently with Benny, including humorous references to his brother Bing's wealth and his string of losing racehorses. Crosby was married and had five children, three girls and two boys.

The enduring popularity of the Bob Crosby Orchestra and the Bob Cats - whose biography was written by British jazz historian John Chilton, was evident during the frequent reunions in the 1950s and 1960s. Bob Haggart and Yank Lawson organized a band that kept the spirit alive, combining Dixieland and swing with a roster of top soloists. From the late 1960s until the mid-1970s, the group was known as The World's Greatest Jazzband. Since neither leader was happy with that name, they eventually reverted to The Lawson Haggart Jazzband. The Lawson-Haggart group was consistent in keeping the Bob Crosby tradition alive.

Bob Crosby died in 1993 due to complications from cancer.