One’s business. The N.E.D. cites Brockett’s ‘Glossary of North-country Words,’ Newcastle-on-Tyne, 1825. “Hash, a sloven, one who does not know how to behave with propriety, a silly talkative person. It is also used in a different sense, though perhaps not local:—

        Brave Prudhoe triumphant shall skim the wide main;
    The hash of the Yankees he’ll settle;
And ages hereafter shall serve to proclaim
    A Northumberland free from Newcastle.”
The phrase in question may have been invented in America, and have been learned by the English in the war of 1812.

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1807.  

        Or should you, for the basest crimes,
Become indicted fifty times,
    This settles all the hash;
For bills, which leave the poor no hope
T’ escape the dungeon or the rope,
    Are cancelled all, by Cash.
Mass. Spy, Oct. 14: from the Albany Register.    

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1824.  The parties settled the hash, (came to an agreement,) and retired to comfortable quarters, to quaff cogniac.—The Microscope, Albany, Feb. 28.

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1837.  I ’ve settled his hash, though, and it won’t cost much hereafter for his messing.—Knick. Mag., ix. 360 (April).

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1849.  I put in what John Sheridan used to call a “sharp left-hander,” which, followed by a short ‘rally,’ completely settled his ‘hash.’—Yale Lit. Mag., xiv. 179 (Feb.).

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1857.  There was mister coon, all safe. I settled his hash, now you ’d better believe, quick!—Knick. Mag., xlix. 69 (Jan.).

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1888.  He was [a know-nothing.] eh? That settles his hash with the German settlement in Crosby Creek.—‘Texas Siftings,’ n.d. (Farmer).

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