Early ex. of "kick someone's [posterior]" = to vanquish (someone).

[Jonathan Lighter]

Many will recall Jimmy Carter's statesmanlilke promise in 1980 that if
Edward Kennedy opposed him in the Democratic primaries, he would "kick his
ass."

Of course, a swift boot in the butt is as likely to be the cause of an
altercation as its finish, so one must consider Carter's expression to be
entirely idiomatic.

An early parallel:

1782 _The Lady's Magazine; or, Entertaining Companion for the Fair Sex,
Appropriated Solely to their Use and Amusement_ XIII (Dec.) 629: She, in
dialogue duett, asks him

" ——How he got 'em."——(_He answers_)

" He drubb'd the Spaniards, bang'd the

French,
" And kick'd Mynheers broad bottom. "


This does not imply, however, that the popular adjective "kick-ass" was in
use at that time.


JL

-- 
"If the truth is half as bad as I think it is, you can't handle the truth."

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