1580s, from un- (1) "not" + past participle of educate (v.).
Entries linking to uneducated
un- 1
prefix of negation, Old English un-, from Proto-Germanic *un- (source also of Old Saxon, Old Frisian, Old High German, German un-, Gothic un-, Dutch on-), from PIE *n- (source of Sanskrit a-, an- "not," Greek a-, an-, Old Irish an-, Latin in-), combining form of PIE root *ne- "not." Often euphemistic (such as untruth for "lie").
The most prolific of English prefixes, freely and widely used in Old English, where it forms more than 1,000 compounds. It underwent a mass extinction in early Middle English, but emerged with renewed vigor 16c. to form compounds with native and imported words. It disputes with Latin-derived cognate in- (1) the right to form the negation of certain words (indigestable/undigestable, etc.), and though both might be deployed in cooperation to indicate shades of meaning (unfamous/infamous), typically they are not.
It also makes words from phrases (such as uncalled-for, c. 1600; undreamed-of, 1630s; uncome-at-able, 1690s; unputdownable, 1947, of a book; un-in-one-breath-utterable, Ben Jonson; etc., but the habit is not restricted to un-; such as put-up-able-with, 1812). As a prefix in telegramese to replace not and save the cost of a word, it is attested by 1936.
educate v.
mid-15c., educaten, "bring up (children), to train," from Latin educatus, past participle of educare "bring up, rear, educate" (source also of Italian educare, Spanish educar, French éduquer), which is a frequentative of or otherwise related to educere "bring out, lead forth," from ex- "out" (see ex-) + ducere "to lead," from PIE root *deuk- "to lead." Meaning "provide schooling" is first attested 1580s. Related: Educated; educating.
According to "Century Dictionary," educere, of a child, is "usually with reference to bodily nurture or support, while educare refers more frequently to the mind," and, "There is no authority for the common statement that the primary sense of education is to 'draw out or unfold the powers of the mind.'"