In 1669 a conventicle, meeting of nonconformists, was reported at Horwich and the ringleaders were prosecuted.
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For the government, in contrast, the whole conventicle movement was seen as a problem of public order, which they attempted to deal with often using very inadequate resources.
From the en.wikipedia.org
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A secret unauthorized meeting for religious worship
A building for religious assembly (especially Nonconformists, e.g., Quakers)
A conventicle is a small, unofficial and unofficiated meeting of laypeople, to discuss religious issues in a non-threatening, intimate manner. Philipp Jakob Spener called for such associations in his Pia Desideria, and they were the foundation of the German Evangelical Lutheran Pietist movement. ...
(conventicles) (n): assembly, meeting. FS (2-2H6, Edw3); Udall Erasmus; Greene Never Too Late; Nashe Absurdity, Penniless; Drayton et al Oldcastle; Chapman D'Olive.
An illegal meeting of non-conformists before 1689.