Background: Louis Thomas Jordan (July 8, 1908 - February 4, 1975) was a pioneering American musician, songwriter and bandleader who was popular from the late 1930s to the early 1950s. Known as "The King of the Jukebox", he was highly popular with both black and white audiences in the later years of the swing era. Jordan was one of the most successful African-American musicians of the 20th century, ranking fifth in the list of the most successful black recording artists according to Joel Whitburn's analysis of Billboard magazine's R&B chart. Though comprehensive sales figures are not available, he had at least four million-selling hits during his career.
Context: Jordan was born on July 8, 1908, in Brinkley, Arkansas, where his father, James Aaron Jordan, was a music teacher and bandleader for the Brinkley Brass Band and for the Rabbit Foot Minstrels. His mother, Adell, died when Louis was young. Jordan studied music under his father, starting out on the clarinet. In his youth he played in his father's bands instead of doing farm work when school closed. He also played the piano professionally early in his career, but alto saxophone became his main instrument. However, he became even better known as a songwriter, entertainer and vocalist. Jordan briefly attended Arkansas Baptist College, in Little Rock, and majored in music. After a period with the Rabbit Foot Minstrels (in which one of his colleagues was Leon "Pee Wee" Whittaker) and with local bands, including Bob Alexander's Harmony Kings, he went to Philadelphia and then New York. In 1932, Jordan began performing with the Clarence Williams band, and when he was in Philadelphia he played clarinet in the Charlie Gaines band. In late 1936 he was invited to join the influential Savoy Ballroom orchestra, led by the drummer Chick Webb. Based at New York's Savoy Ballroom, Webb's orchestra was renowned as one of the best big bands of its day and regularly beat all comers at the Savoy's legendary cutting contests. Jordan worked with Webb until 1938, and it proved a vital stepping-stone in his career--Webb (who was physically disabled) was a fine musician but not a great showman. The ebullient Jordan often introduced songs as he began singing lead; he later recalled that many in the audience took him to be the band's leader, which undoubtedly boosted his confidence further. This was the same period when the young Ella Fitzgerald was coming to prominence as the Webb band's lead female vocalist; she and Jordan often sang duets on stage, and they later reprised their partnership on several records, by which time both were major stars. In 1938, Webb fired Jordan for trying to persuade Fitzgerald and others to join his new band. By this time Webb was already seriously ill with tuberculosis of the spine. He died at the age of 34, after spinal surgery on June 16, 1939. Following his death, Fitzgerald took over the band. Jordan's first band, drawn mainly from members of the Jesse Stone band, was originally a nine-piece group, but he soon scaled it down to a sextet after landing a residency at the Elks Rendezvous club, at 464 Lenox Avenue, in Harlem. The original lineup of the sextet was Jordan (saxes, vocals), Courtney Williams (trumpet), Lem Johnson (tenor sax), Clarence Johnson (piano), Charlie Drayton (bass) and Walter Martin (drums). In his first billing, as Louie Jordan's Elks Rendez-vous Band, his name was spelled Louie so people would know not to pronounce it Lewis. The new band's first recording date, for Decca Records on December 20, 1938, produced three sides on which they backed an obscure vocalist, Rodney Sturgess, and two novelty sides of their own, "Honey in the Bee Ball" and "Barnacle Bill the Sailor". These recordings were credited to the Elks Rendezvous Band, but Jordan subsequently changed the name to the Tympany Five, since Martin often used tympani in performance. (The word tympany is also an old-fashioned colloquial term meaning "swollen, inflated, puffed-up", etymologically related to timpani, or kettledrums, but historically separate.) The various lineups of the Tympany Five (which often featured two or three extra players) included Bill Jennings and Carl Hogan on guitar, the renowned pianist-arrangers Wild Bill Davis and Bill Doggett, "Shadow" Wilson and Chris Columbus on drums and Dallas Bartley on bass. Jordan played alto, tenor and baritone saxophone and sang the lead vocal on most songs. Their next recording date, in March 1939, produced five sides, including "Keep a-Knockin'" (originally recorded in the 1920s and later famously covered by Little Richard), "Sam Jones Done Snagged His Britches" and "Doug the Jitterbug". Lem Johnson subsequently left the group and was replaced by Stafford Simon. Sessions in December 1939 and January 1940 produced two more early Jordan classics, "You're My Meat" and "You Run Your Mouth and I'll Run My Business". Other musicians who passed through the band in 1940 and 1941 included the tenorist Kenneth Hollon (who recorded with Billie Holiday) and the trumpeter Freddie Webster (from Earl Hines's band), who was part of the nascent bebop scene at Minton's Playhouse and influenced Kenny Dorham and Miles Davis. The prime of Jordan's recording career, 1942-1950, was a period of segregation on the radio. Despite this he had a crossover number 1 single, "G.I. Jive" backed with "Is You Is or Is You Ain't My Baby?" in 1944, thanks in large part to his performance with his orchestra of the song in the all-star wartime musical film Follow the Boys (Universal Pictures, 1944). Two years later, MGM's cartoon cat Tom sang "Is You Is or Is You Ain't My Baby?" in the 1946 Tom and Jerry cartoon short "Solid Serenade". Jordan appeared in the 1946 Monogram Pictures movie Swing Parade of 1946 and starred in the 1947 all-black, full-length Astor Pictures film Reet, Petite and Gone. During this period Jordan again placed more than a dozen songs on the national charts. However, Louis Jordan and His Tympany Five dominated the 1940s R&B charts, or (as they were known at the time) the "race" charts. In this period Jordan had eighteen number 1 singles and fifty-four in the Top Ten. According to Joel Whitburn's points-based analysis of Billboard chart placings, Jordan ranks fifth among the most successful artists over the period 1942-1995. From July 1946 through May 1947, Jordan had five consecutive number 1 songs, holding the top slot for 44 consecutive weeks. Jordan's popularity was boosted not only by his hit Decca records but also by his prolific recordings for Armed Forces Radio and the V-Disc transcription program, which helped to make him as popular with whites as with blacks. He also starred in a series of short musical films and made numerous "soundies" for his hit songs. The ancestor of the modern music video, soundies were short film clips designed for use in audio-visual jukeboxes. These were in addition to his part in Follow the Boys. CANNOTANSWER
Question: When did Jordan start being the "King of the Jukebox"?

Answer:

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