It is NOT from:
the Haitian port "Aux Cayes," Louisiana French au quai, a Puerto Rican rum labeled "Aux Quais," German alles korrekt or Ober-Kommando, Chocktaw okeh, Scots och aye, Wolof waw kay, Greek olla kalla, Latin omnes korrecta, bakers stamping their initials on biscuits, shipbuilders marking wood for "outer keel," or Civil War soldiers carrying signs for "zero killed."
It was based on an 1839 joke:
The "Chairman of the Committee on Charity Lecture Bells," is one of the deputation, and perhaps if he should return to Boston, via Providence, he of the Journal, and his train-band, would have his "contribution box," et ceteras, o.k.—all correct—and cause the corks to fly, like sparks, upward.
It wasn't as strange as it might seem for the author to coin OK as an abbreviation for "all correct." There was a fashion then for playful abbreviations like i.s.b.d (it shall be done), r.t.b.s (remains to be seen), and s.p. (small potatoes). They were the early ancestors of OMG, LOL, and tl;dr. A twist on the trend was to base the abbreviations on alternate spellings or misspellings, so "no go" was k.g. (know go) and "all right" was o.w. (oll write). So it wasn't so surprising for someone come up with o.k. for oll korrect. What is surprising is that it ended up sticking around for so long while the other abbreviations faded away.
OK got lucky by hitting the contentious presidential election jackpot. During the 1840 election the "oll korrect" OK merged with Martin van Buren's nickname, Old Kinderhook, when some van Buren supporters formed the O.K. Club. After the club got into a few tussles with Harrison supporters, OK got mixed up with slandering and sloganeering. It meant out of kash, out of karacter, orful katastrophe, orfully confused, all kwarrelling or any other apt phrase a pundit could come up with. It also got mixed up with the popular pastime of making fun of van Buren's predecessor, Andrew Jackson, for his poor spelling. One paper published a half-serious claim that OK originated with Jackson using it as a mark for "all correct" (ole kurrek) on papers he had inspected.
So, I hope you're OK participating in yet another week of our game. Once the Linky goes live, you will be OK to post your musings with us, and our more than OK team will visit you. OK, so you know how this works.