Green’s Dictionary of Slang

King’s Head Inn (in Newgate Street) n.

Newgate prison.

1686		Dorset ‘A Faithful Catalogue of our most Eminent Ninnies’ in Works of Rochester, Roscommon, Dorset (1720) 35: How H---t boasts, that his wise King’s Head Crew / Foretold the dismal Times we all should rue.
c.1698		B.E. Dict. Canting Crew n.p.: King’s Head Inn, or the Chequer Inn in Newgate-street, c. the Prison, or Newgate.
1719		A. Smith Lives of Most Notorious Highway-men, etc. (1926) 207: King’s Head Inn, or Chequer Inn in Newgate-Street, the prison of Newgate.
1725		New Canting Dict.
1737, 1759, 1760, 1776		Bailey Universal Etym. Eng. Dict.
1785, 1788, 1796		Grose Classical Dict. of the Vulgar Tongue n.p.: King’s head inn, or the chequer inn, in Newgate street, the prison of Newgate.
1811		Lex. Balatronicum [as cit. 1785].
1823		Egan Grose’s Classical Dict. of the Vulgar Tongue [as cit. 1785].
1836		W.H. Smith ‘The Thieves’s Chaunt’ in Farmer Musa Pedestris (1896) 121: But because she lately nimm’d some tin, / They have sent her to lodge at the King’s Head Inn.