There is an obscure Old English text, Solomon and Saturn, which credits Woden, the chief deity amongst the Germanic people, with the establishment of letters:
saga me, hwá aeróst bócstasfas sette?
ic the secge, Mercurius ge gygand.
“Tell me, who first established letters?
I tell thee, Mercurius the giant.”
The exerpt from Solomon and Saturn above also coincides with verses 138-139 in the Hávamál, which credits Woden with the discovery of the runes. The name Mercurius above is the original Latin form of Mercury, who we know was identified with Woden since the time of Tacitus (c. 56-120 AD), and was worshipped as the highest god amongst the Germans:
"Of the gods, Mercury (Odin) is the principal object of their adoration; whom, on certain days, they think it lawful to propitiate even with human victims. To Hercules (Thor) and Mars (Tyr), they offer the animals usually allotted for sacrifice..."
-Tacitus, Germania
Moreover, in his Annals, Tacitus wrote of how war broke out between the Hermunduri and the Chatti over a salt bearing river. He notes that each side vowed to sacrifice the other to Mars and Mercury for victory.
In sources as late as the 12th century, such as The History of the Kings of Britain by Geoffrey of Monmouth (c. 1095-1155), the identification of Mercury as Woden is further exemplified. Geoffrey writes in reference to Hengist, the leader and first king of the Jutes in Kent, that they "...especially worship Mercury, whom we call Woden."
Additionally, Layamon's Middle English poem Brut - which was largely influenced by the Anglo-Norman poet Robert Wace's Roman de Brut (1155) - states that Hengist once said that Woden is the highest of Gods. From this, we can gather that the Roman equivalent of Woden was Mercury (Greek: Hermes). This identification was preserved in later medieval sources, and continues to serve as an interesting point of study regarding the religion of the pre-Christian Germanic peoples.
Maybe this book would be informative in regards of Mercurius/Hermes:
https://books.google.hu/books/about/Hermes_Guide_of_Souls.html?id=dxYSAQAAIAAJ&redir_esc=y
What a fascinating connection! What do you think about the idea of Mercury as a messenger god re: Odin's ties to him?