Among the Igbo people, Ghanaian highlife became popular in the early 1950s, and other guitar-band styles from Cameroon and Zaire soon followed. The Ghanaian E. T. Mensah, easily the most popular highlife performer of the 1950s, toured Igbo-land frequently, drawing huge crowds of devoted fans. Bobby Benson & His Combo was the first Nigerian highlife band to find audiences across the country. Benson was followed by Jim Lawson & the Mayor's Dance Band, who achieved national fame in the mid-'70s, ending with Lawson's death in 1971. During the same period, other highlife performers were reaching their peak. These included Prince Nico Mbarga and his band Rocafil Jazz, whose "Sweet Mother" was a pan-African hit that sold more than 13 million copies, more than any other African single of any kind. Mbarga used English lyrics in a style that he dubbed panko, which incorporated "sophisticated rumba guitar-phrasing into the highlife idiom".