From the band's own website http://www.macumba.com:
MacUmba are a unique group of musicians based in Scotland who mix the traditional sounds of Scottish bagpipes with the infectious rhythms of Brazilian percussion. Starting as a batucada (or drumming group) in the early 90's, MacUmba grew out of a series of drumming workshops held at the Glasgow School of Art. Soon after, MacUmba added various combinations of flutes, guitars, bass, voices etc. to the batucada, and performed at many events throughout Scotland.

Read more about Macumba on Last.fm.