I am not sure when the “Illuminati” symbols of the eye and the pyramid became popular. I assume it was when “Pop Culture” became a thing. The pyramid and the eye, as seen below, were added to the dollar bill as part of “The Great Seal Of The United States” in 1935. What you see below is on the left side of the dollar.
Nobody in the Conspiracy Circles really talk about it other than to say it comes from Freemasonry and Freemasonry has mythical origins.
However, I did find an image that bears resemblance to the to today’s pyramid and eye on a copy of “Selected Writings From The Talmud,” the Babylonian Talmud.
The Babylonian Talmud was the original Talmud. It was first developed while the Jews were in captivity in Babylon. As far as I know, this was the first time they codified the mixing of their religion and laws with another nation’s.
Amazon here, says that the picture is a piece of artwork in the pavement at a Synagogue called the Beth Alpha Synagogue. It has been there since the 6th Century.
What it means in the grand scheme of things, that will have to be further researched