Green’s Dictionary of Slang

Roman Catholics, seen as a group.

1785, 1788, 1796		Grose Classical Dict. of the Vulgar Tongue.
1798		Sporting Mag. Oct. XIII 51/1: A London paper informs its readers, that all the United Irishmen resident in Paris, are on board the Brest [sic] fleet.
1811		Lex. Balatronicum.