Tango originated in late 19th century Buenos Aires, Argentina among African slaves and European immigrants. It combined elements of African, European and Cuban dance and was popularized in dance halls and among all classes in Argentina in the early 1900s. The style then spread to Europe and the US, developing distinct ballroom and Argentine styles. Key tango composers included Roberto Firpo, who brought romance to the style, and Astor Piazzolla, a major innovator who transformed tango with elements of jazz and classical music. Tango is danced in close embrace to music featuring accented, syncopated rhythms played by instruments like bandoneón, violin and piano at a moderate tempo.