Seren tan gwmmwl, neu ychydig sylw ar frenhinoedd, escobion, arglwyddi, &c. a llywodraeth Lloegr yn gyffredin. Wedi ei ysgrifennu er mwyn y Cymru uniaith

Jac Glan-y-Gors (John Jones) was a satirical writer and inn keeper. The author’s aim in this published pamphlet was to present Thomas Paine’s ideas to a wider Welsh speaking audience. Jones shared Paine’s values on war, monarchy, the Established Church and the rights of men. These values are demonstrated in ‘Seren tan Gwmwl’. He played a prominent role within the London-Welsh societies at the end of the eighteenth century and co-founded the Cymreigyddion Society.