The expression “like a bear with a sore head” means: Very disgruntled; peevish; ill-tempered; soreheaded.
Professor Hans Sperber of Ohio State University, in his studies of words and phrases in American politics, argues that the American term “sorehead,” meaning a disgruntled person, is derived from the metaphor, “like a bear with a sore head” (American Speech, Vol. XXVII).
To add point to the argument he cites some uses of a century and more ago: Cincinnati Gazette, October 26, 1824, “The engineer, Dawson, a pussy fatwitted Irishman, was raving round the forecastle like a bear with a sore head, ever and anon vociferating corruption,” and W. G. Simms, The Partisan (1835),
“Art thou, now, not a sorry bear with a sore head, that kindness cannot coax, and crossing only can keep civil!” Then he goes on through the years with other quotations which lend support to his contention that the “bear with a sore head” became the source of the political term, “sorehead,” used first in the campaign of 1848, “when the opponents of the newly founded Free Soil party characterized it as a motley crowd recruited from the refuse of other parties,” demonstrated by a quotation from the Albany Weekly Argus, August 12th of that year:
“As no other selection could be supposed so well to represent such a conventicel (sic) of ‘sore heads,’ it is perhaps quite as well it sho’d take direction as any other.”
Although Professor Sperber modestly admits that he has indulged in a certain amount of guesswork in his etymology, his circumstantial evidence is nevertheless convincing. Regrettably, the origins of slang and colloquial expressions are rarely recorded at birth; consequently, later researchers are often obliged to resort to conjecture.
But Professor Sperber assumes in his discussion that the expression, “a bear with a sore head,” grew out of the experience of hunters who learned that shooting a bear in the head was likely to lead to nothing more than to make the animal truculent, highly irascible and fighting mad.
We doubt that explanation, though it stands to reason that any animal, bear or other, so injured by a non-fatal shot would not be exactly jovial. We suggest, therefore, though we have no record to prove it, that the metaphor arose belatedly either from bear-baiting, in which dogs were set upon a bear chained to a stake, or from the ancient tales of Reynard the Fox.
You will recall that one of these tales relates how Reynard greatly discomfited Bruin by leading him to a succulent repast of honey, which, however, was stored in a cleft of a tree.
When Bruin inserted his head to gorge upon the honey, the fox slyly removed the wedge left by the woodsman, and then led the farmer to the scene.
Bruin made his escape only at the expense of losing most of the skin from his head, and was indeed “a bear with a sore head” when he returned to court.