Forseti is a Germanic pagan god numbered among the Aesir who lives in a hall called Glitner, and he is well-known for making peace. From Grimnismal 15:
15. The tenth is Glitnir; | its pillars are gold,
And its roof with silver is set;
There most of his days | does Forseti dwell,
And sets all strife at end.
This description is the only mention of Forseti in the collection of poems we now call the Poetic Edda. It’s my belief that the Poetic Edda is the most reliable of our sources of understanding on the mythological structure of the pre-Christian Germanic religion, so it’s disappointing that a god important enough to have a splendid hall and responsibilities clearly important to everyday life would have had so few references survive.
It’s at least worth pointing out the context within Grimnismal itself. As Henry Adams Bellows explains in an introductory note to the translation quoted above, this is a mostly encyclopedic poem with a couple of quick prose notes as bookends to show that Odin, under an alias, has been captured and is being tortured, and is providing a long list of names and places to show his captor, and his captor’s son, that they are holding an extraordinary prisoner. At the end of the tale, Odin breaks free of his bonds and kills the foolish king, leaving his son to learn the necessary lessons, mythological and metaphorical.
Because the actual text of the poem is really just a long list in meter, as you see above, it’s pretty clear the point of the poem isn’t to entertain, but rather to educate. This poem would be recited, memorized, and passed on to the next generation, over and over again, so that knowledge of the gods and their dwellings (etc.) would survive. The sugary Odin coating is just to make the dish a bit more palatable. Who wants to learn something if there’s not any fighting or dying in the story?
But as I said, the Poetic Edda is the most reliable source, not the only source. The name “Edda” comes from the prose book written by Icelandic scholar Snorri Sturluson, and was only retroactively applied to the poems he frequently referenced, which were found in different manuscripts entirely. We have good reason to question things Snorri has to say about the pre-Christian Germanic gods, kings, and heroes: he was writing nearly 300 years after Iceland converted to Christianity; he was himself a Christian, and explicitly Euhemerized his account of the Norse mythology: he explained that the gods were not really gods, but merely famous men about whom the legends grew god-sized. His purpose was not to preserve religious knowledge, but to explain how these old forms of poetry had worked, what their references were about, and a contemporary poet might use that style, and those references, for himself.
That’s not to say that we should throw out everything Snorri has to say, just that we have a bit more room to doubt. He was a poet, and sometimes took license with his creation to help things fit what he thought would be pleasing.
So what does Snorri have to say about Forseti? In Gylfaginning XXXII, he writes,
Forseti is the name of the son of Baldr and Nanna daughter of Nep: he has that hall in heaven which is called Glitnir. All that come to him with such quarrels as arise out of law-suits, all these return thence reconciled. That is the best seat of judgment among gods and men; thus it is said [continues to reproduce Grimnismal 15 verbatim].
Since Baldr is one of the most important of the Norse gods, and this paragraph heavily indebted to Grimnismal 15, we have to take Snorri’s claim here seriously. But we don’t have any other reason to believe there is an association between Forseti and these better-known gods. Baldr and Nanna have more links to fertility and agriculture than they do to anything involving peace or arbitration. Thor’s sons are powerful like their father; Odin’s are warriors, one of whom avenges his father. Maybe that’s not a productive path to knowledge of Forseti.
It looks like “forseti” is an Old Norse word meaning “chairman” or “presiding one”. It’s come to mean “president” in modern Icelandic. This suggests an even stronger connection for Forseti with the ancient legal system, to the extent that term applies, and to jarls and kings, putting him in a class of gods with Odin and Tyr in particular. It may be that this was well-understood when the Aesir were originally worshiped, and that each had a well-understood role as animating forces of the community. As it is, there’s already some confusion about how Odin and Tyr form two faces of the idea of justice; with Forseti involved in resolving disputes and most likely leading decision-making sessions, the picture is a bit more muddled.
It may help to have a basic understanding of the þing, or “Thing”, an important part of the government of most Germanic peoples. The Thing was an early form of democratic assembly, where all the free men (just men, and slaves were excluded) in a community would meet together and make decisions about issues of public concern. In this assembly, chiefs, jarls, and kings were elected. The laws that governed the community were proposed, discussed, and put into place. Where peoples were aligned into larger kingdoms, local Things sent representatives to the regional Thing.
Perhaps the most important person in any Thing was the “law speaker,” a person who memorized all the laws of the community and recited them as necessary. The law speaker would necessarily be asked to make decisions about interpretations of law as the expert upon it.
The Thing is actually explicitly mentioned as a practice of the Aesir by the Poetic Edda (Hymiskvitha 40; Thrymskvitha 13; Baldrs Draumar 1; etc.), which makes it clear that this practice was not only something the peoples of Viking Age (and earlier) Northern Europe did for themselves, but its what they considered to be the natural order of things, how the gods worked out their problems and made decisions about everything affecting the Aesir and all the realms. And of course the Thing lives on today, not only by name as the Althing in Iceland (they’ve been busy lately), but as a variety of democratic institutions in Northern Europe and around the world where societies have adopted European-style democratic institutions, though obviously debts are owed to other ancient democratic institutions as well.
Forseti then was most likely understood by Snorri, and by the Germanic pagans who preceded him, to be the law speaker in the Aesir’s Althing. While we don’t have direct textual evidence of that, the combination of the name, the textual evidence for Forseti and the Aesir, and the evidence from social institutions running from ancient times through Snorri’s time all the way to today seems to make this very likely. When Forseti was resolving disputes in his hall Glitner, it was probably handling minor questions of law and how people might proceed in certain circumstances, saving more major issues for the Althing, to be decided by all the Aesir, or perhaps by Odin in situations where executive leadership was necessary.
The exact role a god with this kind of mythological underpinning might have in the daily religious lives of those who worshiped the Aesir is unclear. Perhaps he was invoked in the Thing as a trusted guide; perhaps the law speakers of early Things took oaths related to Forseti. There’s some evidence that Forseti may even have been worshiped in a place or two as a local patron god. It certainly seems likely that in ancient times, Forseti was better-known to believers in the Aesir than these few meager references to him would suggest. The fact that we aren’t as familiar with his name as we are with Thor’s, Odin’s, or Tyr’s doesn’t mean he wasn’t spoken of regularly.
So perhaps it’s worth remembering that there is actually a heathen god who we can associate with institutions of democracy and resolving disputes, even if it’s hard to say with certainty any more about him than that he lives in shiny house. I mean, he’s Northern Europe’s first lawyer, so he’s got to have a nice house, right?