Green’s Dictionary of Slang

1. (US) an Irish-American Catholic whose forebears come from Northern Ireland; thus fardownianism.

1834		Baltimore Eve. Star 20 June 20 2/5: [headline] The Corkonians, or Longfords, and the Fardowns again.
1838		Commercial Advertiser (N.Y.) 3 May 2/4–5: In the morning there was a match fight between two bullies, one a ‘Far-Down’ and the other a ‘Corkonian’. [Ibid.] 2/5: They may talk of Far-Downism, Corkonianism, Catholicism, Protestantism, and all the other isms which are supposed to lead to these outrages.
1846		D. Corcoran Picking from N.O. Picayune 67: ‘Divil burn him,’ says Mick, ‘I took him for a Fardown and [...] laid him as flat as a pancake.’.
1851		Manchester Spy (NH) 17 May n.p.: They were pounced upon by about twenty Irish cut throats [...] Whether they were the atriotic ‘Far-downers,’ ‘Corkonians’ or sheep-stealers we know not which.
c.1880		‘Drill You Tarriers, Drill’ 🎵 The boss was a good man all around, / ’Till he married a great big fat far down.
1931		(con. 1900s) C.W. Willemse Behind The Green Lights 135: ‘Not only does he bless me, but he invites me to come and se him. Think of that, and me a Far Down.’ A Far Down being an Ulsterman.

2. (Aus.) Ulster.

1890		Bulletin (Sydney) 16 Aug. 15/2: You who are Scotch and those who come from the Far-down never know well wherein that guide is summarily comprehended.
1898		F.P. Dunne Mr Dooley in Peace and War viii: In this community you can hear all the various accents of Ireland, from the awkward brogue of the ‘far-downer’ to the mild aisy Elizabethan English of the southern Irishman.