George Fox 1624-1691, founded Religious Society of Friends about 1652 in England. He taught how to worship in silence. At their monthly meetings a follower only spoke when he felt moved by the "Holy Spirit", some meeting went the whole hour without anyone speaking.
Mr. Fox was persecuted all his life and jailed many times. Once, when he was dragged into court he shout to the judge "tremble at the word of the Lord", the judge sarcastically referred to Fox as a "Quaker". From then on the name became the most popular for the Religious Society of Friends.
The following links have more Quaker information: