What were the fists of righteous harmony or Boxers rebelling against?

Their cause, at first, was to overthrow the imperial Ch'ing government and expel all "foreign devils" from China. The crafty empress, however, saw a way to use the Boxers. Through her ministers, she began to encourage the Boxers. Soon a new slogan -- "Support the Ch'ing; destroy the foreigner!" -- appeared upon the Boxers' banner.