The newspaper refered to a senator in high dudgeon.

Where does this phrase come from?

What is a 'dudgeon'? Do we ever use that word, except in this phrase? If not, any idea why it died out - or why this particular phrase survived?

A "dudgeon" appears to be a hilt of a dagger, possibly made from wood. How this relates to "high dudgeon", I'm not sure.

The OED Online says dudgeon is "A kind of wood used by turners, esp. for handles of knives, daggers, etc," (1380) "The hilt of a dagger, made of this wood," (1605) or "Hence dudgeon-dagger, and in later use dudgeon: A dagger with a hilt made of ‘dudgeon’; also, a butcher's steel. arch (1581).

It's also "feeling of anger, resentment, or offence; ill humour. Almost always in phr. in dudgeon, and esp. with qualifying adj., as high, great, deep (1573)."

The origins are unknown, though the first appears to be French, and apparently are not related. The Online Etymology Dictionary says pretty much the same thing.

The AHD and Dictionary.com Unabridged agree, giving slightly different dates. Indignation and pique are given as synonyms.

Tiinman

"Almost always in phr. in dudgeon"

dictionary.com gives a 1999 cite without the "in". I'd never heard of it this way.

What you see, they reckon, is all there is: a media star of fading allure--and shortening temper, if his dudgeon over a television soap-opera satire about him called "How was I, Doris?" (a reference to his fourth wife) is anything to go by.
-- "Gerhard Schröder, embattled chancellor", The Economist, September 18, 1999