Green’s Dictionary of Slang

1. (US) pertaining to Baptists, of the primitive Baptist Church.

1838		in S.W. Hist. Quarterly XVII 54: Was introduced to Daddy Spraggins, a Hardshell Baptist preacher [DA].
1845		J.J. Hooper Adventures of Captain Simon Suggs (1851) 13: He lived with his father, an old ‘hard shell’ Baptist preacher.
1853		in R. Glisan Journal Army Life (1874) 123: His first two sermons sounded very much like good old hard shell baptist harangues.
1859		Elgin Courier 9 Sept. 3/4: A ‘whang doodle,’ hard-shell preacher wound up a flaming sermon [etc.].
1864		J.W. Haley Rebel Yell and The Yankee Hurrah (1985) 250: Hayden was a Baptist of the hard-shell persuasion.
1871		E. Eggleston Hoosier School-Master (1892) 133: Squire Hawkins, having been expelled from the ‘Hardshell’ church [...] for the grave offence of joining a temperance society.
1885		Bulletin (Sydney) 5 Sept. 26/1: A hardshell Gospel-purveyer has had the Briagolong (Gippsland, Vic.) people on the baptism-by-water string.
1887		G. Davis Recoll. Sea-Wanderer 369: His brother Ben married a daughter of a neighbor, and joined the church (hard-shell Baptist).
1891		F.D. Srygley Seventy Years in Dixie 212: In the early days, Hard-shell Baptists, as they were called, were the dominant religious party.
1900		Congressional Record 31 Jan. 1363/2: One of the best old preachers that ever I knew [...] was a Hardshell Baptist [DA].
1916		Renton & Tunnah ‘Pray For The Lights To Go Out’ 🎵 Father was a deacon in a hard shell church.
1927		(con. 1918) J.J. Niles Singing Soldiers 40: You has colored folks about you callin’ ’emselves ‘hardshell Baptists’.
1930		(con. 1870s) in S. Henry Conquering Our Great Amer. Plains 185: It almost makes a hard-shell Baptis’ like me (a wink) sniffle to see these loony aggerculturalists.
1940		(con. 1820s) W.E. Wilson Wabash 224: An imitation of the new brimstone peddler at the Old Pigeon Hard-Shell Baptist Church.
1947		(con. 1944) J.H. Burns Gallery (1948) 102: I’m only a Hard-Shelled Baptist.
1952		Lait & Mortimer USA Confidential 213: Two-thirds of the vast Lone Star State is hard-shell Baptist.
1963		F. Kohner Affairs of Gidget 31: Compared to this doll, Dr. Gottfried Hofer was a hard-shell Ammanite.
2000		C. Cook Robbers (2001) 11: He’s a hardshell Baptist an thinks this ride is the big banana.

2. (orig. US) uncompromising, fundamentalist, unswervingly conservative.

1853		N.Y. Clipper 8 Oct. 3/5: At the great gathering of the hard shell section of the Democracy on Monday [etc].
1872		Holmes Co. Repub. (Millersburg Co., OH) 18 July 3/3: The ghastliest thing we ever saw was a hard-shell Democrat trying to wear a Greeley hat.
1905		Sporting Times 4 Mar. 2/3: Admitting the hardshell fact that it was still only the first day of March.
1916		C.J. Dennis ‘The Push’ in Moods of Ginger Mick 38: An’ Ginger – ’ard-shell Ginger’s showin’ signs that ’e will pay; / But it took a flamin’ world-war fer to blarst ’is crust away.
1919		J. Buchan Mr Standfast (1930) 783: If I weren’t a hard-shell Presbyterian I’d say a prayer for his soul.
1922		Morn. Tulsa Daily World (OK) 17 Dec. 74/5: To the old man stealing was quite legitimate. He wouldn’t have countenanced immorality of the sort his hard-shelled scruples balked against.
1943		J. Mitchell McSorley’s Wonderful Saloon (2001) 32: She is disliked by many of the hard-shell evangelists who hold hymn-singings in the gutters of the Bowery.
1962		S. Longstreet Flesh Peddlers (1964) 325: You’re a hard-shelled bastard.
1977		B. Jackson Killing Time 197: I try not to have barrel vision. I try to look at both sides. I try not to be so hard-shell conservative, you know, that I can’t think outside of that.