In 1923 William leaves the orphanage and hits the road. He will spend next few years hoboing.
By 1939 and now in Indianapolis, William enjoys success as a pianist in that city's clubs. The following year, after 107 bouts as a boxer he quits the sport. But a new phase in his life begins when he is spotted by Lester Melrose of the OKeh record label and he has his first recording session in Chicago in June. William is also now known as 'Champion Jack', probably in tribute to boxer Jack Johnson.
In 1941 after 18 months of making records he returns in triumph to New Orleans where he plays at the Lincoln Theatre. Then he is drafted into the US Navy as a cook in 1942, a service which lasts until 1945 when he is discharged in New York and he decides to stay.
After eight years recording for small independent labels, Champion Jack signs for the King label in 1953 and will record for them exclusively for next two years. He enjoys a hit with 'Walking the Blues', a fun number, with Teddy 'Mr Bear' McRae.
Jack moves to the RCA record label in 1956 where he makes two further versions of 'Walking the Blues'. He makes his last LP Blues from the Gutter, before leaving the USA for Europe. It turns out to be a classic.
He is invited to play in Britain in 1959 and decides to remain in Europe. He marries a British woman and the couple live in Britain, Switzerland and Denmark.
In 1964 Jack works with Chris Barber.
Having moved to Sweden in 1976 and with a new woman, Jack has his paintings exhibited in Stockholm. A year later he makes his final move in Europe, basing himself in Hanover, Germany, where he works as a cook in a club.
He plays at the New Orleans Jazz and Heritage Festival in 1990 and again in 1991 as well as the Chicago Blues Festival.
Champion Jack Dupree dies of cancer in Hanover, Germany on 21st January 1992.