The decrease in the native American rituals and celebrations was because they were They were outlawed by the American government.
The Native Americans were the ones that were the original occupants of America. They were the ones that owned the lands before they were pushed out and the areas were occupied by the Americans.
They used to have a lot of ceremonies. An example of this is the ghost dance. These got to be outlawed because the Americans felt that they may lead them to become violent again.
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