Slingsby Bethel was born in Alne, Yorkshire and baptized on 27 February 1617. He died in February 1697. The third son of Sir Walter Bethel and Mary Slingsby (hence his name), Bethel was educated at home for a career in commerce. From 1637 to 1649, he worked in Hamburg. His business success, frugality and an inheritance enabled him to acquire considerable property in Yorkshire. During the civil wars and the Protectorate, he was an Independent, equally hostile to both Royalists and Cromwellians, as evidenced in his A True and Impartial Narrative (1659). As MP for Knaresborough in 1659, he opposed Richard Cromwell's attempt to succeed his father as Protector. He also opposed General Monck and the Restoration (1660). He moved to Rotterdam, communicated with the English republican exiles gathered around Edmund Ludlow in Switzerland, and plotted an uprising in England with Algernon Sidney and others. The revolutionaries were divided, a division deepened by Bethel's attack on Cromwell in his first major pamphlet, The World's Mistake in Oliver Cromwell (1668). His second was The Present Interest of England Stated (1671).
From The Continuum Encyclopedia of British Philosophy in Oxford Reference.