Willie Jason Mabon, born on October 24, 1925, in Hollywood, Tennessee, was an American R&B singer-songwriter, pianist, and harmonica player. He moved to Chicago in 1942 and in 1949 began recording for Aristocrat Records and later Chess Records. Mabon's breakthrough came with his debut solo release "I Don't Know" in 1952, which topped the Billboard R&B chart for eight weeks. This success was followed by another hit, "I'm Mad", in 1953 and the notable song "Poison Ivy" in 1954. Despite initial successes, his career saw a decline in the late 1950s and 1960s. He moved to Paris in 1972, where he toured and recorded as part of Jim Simpson's American Blues Legends tour. Mabon performed at the Montreux Jazz Festival before his death on April 19, 1985, in Paris.