1839, only survivor of a slang fad in Boston and New York -9 for abbreviations of common phrases with deliberate, jocular misspellings (. . for "no go," as if spelled "know go;" . for "'nuff ced;" . for "know yuse"). In the case of . , the abbreviation is of "oll korrect."
Probably further popularized by use as an election slogan by the . Club , New York boosters of Democratic president Martin Van Buren's 1840 re-election bid, in allusion to his nickname Old Kinderhook , from his birth in the . village of Kinderhook. Van Buren lost, the word stuck, in part because it filled a need for a quick way to write an approval on a document, bill, etc. Spelled out as okeh , 1919, by Woodrow Wilson, on assumption that it represented Choctaw okeh "it is so" (a theory which lacks historical documentation); this was ousted quickly by okay after the appearance of that form in 1929. Greek immigrants to America who returned home early 20c. having picked up . speech mannerisms were known in Greece as okay-boys , among other things.
The noun is first attested 1841; the verb 1888. Okey-doke is student slang first attested 1932.