On New Year's Day, a poster asked How, when and where did the phrase 'state of the art' originate? Unfortunately, those words were the entirety of both the question header and the question body—and the question was (not inappropriately) closed for lack of research effort. As far as I can tell, the poster never supplied any evidence of additional research into the question.
Before it was closed, the question drew two useful answers suggesting fairly late first-occurrence dates for "state of the art" as a phrase equivalent to "status of the art" (late 19th century), "state of the art" as a phrase equivalent to "stage of development of a practical or technological subject," and "state-of-the-art" as an adjective phrase (1955). All of these datings are attributed to OED.
A quick Google Books check, however, turned up an instance of "state of the art" in the sense of "status of the art" from 1776—a century before the reported OED suggestion of late 19th century. I have altered the OP's question to note that occurrence, and I think it would be interesting to see what other early occurrences for each sense of the phrase may be findable. But first the question needs to be reopened. It's a classic case of a potentially interesting question disabled by the poster's lack of effort. Please consider reopening this question.