This page documents some of the earliest known examples of Hermetic and Illuminati symbols. In order to keep the page at a manageable size there is little or no discussion of the meaning of each symbol.
Egypt, pre 3,000 BCE
Wadjet (green one) was originally the ancient local goddess of the city of Dep (Buto), which became part of the city that the Egyptians named Per-Wadjet, House of Wadjet, and the Greeks called Buto (Desouk now), a city that was an important site in the Predynastic era of Ancient Egypt and the cultural developments of the Paleolithic. She was said to be the patron and protector of Lower Egypt and upon unification with Upper Egypt, the joint protector and patron of all of Egypt with the "goddess" of Upper Egypt. The image of Wadjet (a cobra) with the sun disk is called the uraeus, and it was the emblem on the crown of the rulers of Lower Egypt. She was also the protector of kings and of women in childbirth. Wadjet was closely associated in the Egyptian pantheon with Bast, the fierce goddess depicted as a lioness warrior and protector, as the sun goddess whose eye later became the eye of Horus, the eye of Ra, and as the Lady of Flame. 
Mesopotamia, c. 3,000 BCE
Several ancient cultures had green deities, often with some features in common with the famous Green Man. These include: Humbaba, the ancient Sumerian guardian of the cedar forest, as well as Enkidu, the wild man of the forest in Sumerian mythology, both of which date back to at least 3000 BCE; the Egyptian corn-god Osiris, who is often depicted with a green face representing vegetation and rebirth; Attis, a Phrygian god of vegetation and Nature; the Tibetan Buddhist deity Amoghasiddhi; the Hindu demon Kirtimukha; Tlaloc, the Aztec god of rain, fertility and water; and several others. Some of the features incorporated into ancient representations of these gods reappear centuries later in the Green Man. For example, the Face of Glory of the Hindu Kirtimukha is usually shown with a mouth issuing leaves, notably missing a lower jaw, and there are several similar representations of a jawless green man in Europe. 
Egypt, c. 2,600 BCE
In Ancient Egypt, the symbol Behedeti is attested from the Old Kingdom (Sneferu, 26th century BC), often flanked on either side with a uraeus (cobra). In early Egyptian religion, the symbol Behedeti represented Horus of Edfu, later identified with Ra-Harachte. It is sometimes depicted on the neck of Apis, the bull of Ptah. As time passed (according to interpretation) all of the subordinated gods of Egypt were considered to be aspects of the sun god, including e.g. Khepri. 
Mesopotamia, c. 2,200 to 2,025 BCE
The oldest known representation of two snakes entwined around a rod is that of the Sumerian fertility god Ningizzida. In the Louvre, there is a famous green steatite vase carved for king Gudea of Lagash (dated variously 2200–2025 BCE) with an inscription dedicated to Ningizzida. 
Egypt, c. 1,400 BCE
The first known appearance of the ouroboros motif is in the Enigmatic Book of the Netherworld, an ancient Egyptian funerary text in KV62, the tomb of Tutankhamun, in the 14th century BC. 
Sumer, 883 to 859 BCE
According to the British Museum  the freestanding gypsum monument, below, was erected by King Ashurnasirpal II who reigned from 883 to 859 BCE in Nimrud (ancient Kalhu), northern Iraq.
A close up of the stele shows the symbols in detail.
Descriptions of the numbered symbols above are as follows:
- The Star of Ishtar, also known as The Star of Venus - see the British Museum description of the Tablet of Samash 
- Pair of compasses, as used by the Freemasons, presumably to represent the geometric plan of the universe
- Crescent moon
- The sun
- Mitre topped with a fleur de lis
- Cross pattee, as used by the Knights Templar and the Pope and on the British Crown Jewels.
- Another star
- A flower
The British Museum claims that #2 above represents "the fork", which is the "thunderbolt of the storm god". I will leave you to decide if they are correct. I suspect they are protecting the origin and secrets of Freemasonic symbols because I've not seen fork lightening with a handle on top before.
Mesopotamia, 721-705 BCE
Seals of the early first millennium B.C. in Babylonia and Assyria were carved in the linear, drilled, cut, and modeled styles. The modeled style illustrated here derives from earlier Middle Assyrian seal carving and from the modeled sculpture in the palace of Sargon II (r. 721–705 BCE), king of Assyria at Khorsabad. This style was used predominantly on seals showing scenes of contest and worship. On this cylinder seal, a statue of the goddess Ishtar stands on a platform within a canopied enclosure. Ishtar is identified by crossed quivers, a starred crown, and stars encircling her body. Two winged genies with wings, and each with a fleur de lis on top of their heads, protect the enclosure, while a kneeling figure worships. http://www.metmuseum.org/toah/works-of-art/1989.361.1
France, c 400 CE
The earliest example of a green man disgorging vegetation from his mouth is from St. Abre, in St. Hilaire-le-grand, c 400 CE . There are over 110 green men carved in Rosslyn Chapel , which means William Sinclair was stressing the message of this symbol above all others. The symbol tells people not to look for evidence of a God separate from the universe, but instead to look for God within all creation (nature).
In 1786, for the first two issues of Columbian Magazine, Philadelphia engraver James Trenchard wrote articles on the obverse (in September 1786) and reverse (in October 1786) of the Great Seal of the United States, and each issue included a full-page engraving of his own original version of the discussed side of the seal. The reverse featured an elongated pyramid with the requisite mottos and the Eye of Providence (a right eye, unlike versions which followed). While not official, Trenchard's depiction had an obvious influence on subsequent official versions, and was the first known public rendering of the reverse side (and only one for many years). 
- Wikipedia, Wadjet, 20 May 2013, http://en.wikipedia.org/wiki/Wadjet
- The Enigma Of The Green Man, Theories and Interpretations, 23 December 2012, http://www.greenmanenigma.com/theories.html
- Roman Empire, Ancient Hatra by Thomas Twohey, March 03, http://www.roman-empire.net/articles/article-036.html
- Wikipedia, Winged Sun, 23 March 2013, http://en.wikipedia.org/wiki/Winged_sun
- Wikipedia, Serpent Symbolism, 24 December 2012, http://en.wikipedia.org/wiki/Serpent_%28symbolism%29
- ferrebeekeeper, Sumerian Double Helix Snake God, 24 December 2012, http://ferrebeekeeper.wordpress.com/tag/ningizzida/
- Wikipedia, Ouroboros, 23 December 2012, http://en.wikipedia.org/wiki/Ouroboros
- touregypt.net, An Enigmatic Book of the Netherworld From A Shrine of Tutankhamun, 23 December 2012, http://www.touregypt.net/featurestories/enigmatic.htm
- The British Museum Images, Stela of Ashurnasirpal II, 23 December 2012, http://www.bmimages.com/preview.asp?image=00029940001
- Flickr, Photos, Helen Sanders, 23 December 2012, http://www.flickr.com/photos/helensanders/5815110188/
- Flickr, Photos, menesje, 23 December 2012, http://www.flickr.com/photos/menesje/2386597193/in/set-72157621922678608
- The Metropolitan Museum of Art, Cylinder seal and modern impression: Ishtar image and a worshipper below a canopy flanked by winged genies, 20 May 2013, http://www.metmuseum.org/toah/works-of-art/1989.361.1
- Wikipedia, The Green Man, 23 December 2012, http://en.wikipedia.org/wiki/Green_Man
- The Big Picture, William Sinclair, 1410–1484, 23 December 2012, http://www.the-big-picture.org.uk/wp/?page_id=3912
- The Green Man and Religion, 23 December 2012, http://www.padrepardo.eu/GM.html
- Wikipedia, Great Seal of the United States, 20 May 2013 http://en.wikipedia.org/wiki/Great_Seal_of_the_United_States#James_Trenchard_engravings