As jazz spread around the world, it drew on national, regional, and local musical cultures, which gave rise to different styles. New Orleans jazz began in the early 1910s, combining earlier brass-band marches, French quadrilles, biguine, ragtime and blues with collective polyphonic improvisation. In the 1930s, heavily arranged dance-oriented swing big bands, Kansas City jazz, a hard-swinging, bluesy, improvisational style and Gypsy jazz (a style that emphasized musette waltzes) were the prominent styles. Bebop emerged in the 1940s, shifting jazz from danceable popular music toward a more challenging "musician's music" which was played at faster tempos and used more chord-based improvisation. Cool jazz developed near the end of the 1940s, introducing calmer, smoother sounds and long, linear melodic lines.