Forseti (Old Norse "the presiding one," actually "president" in Modern Icelandic and Faroese) is an Æsir god of justice and reconciliation in Norse mythology. He is generally identified with Fosite, a god of the Frisians. Jacob Grimm noted that if, as Adam of Bremen states, Fosite's sacred island was Heligoland, that would make him an ideal candidate for a deity known to both Frisians and Scandinavians, but that it is surprising he is never mentioned by Saxo Grammaticus.
Grimm took Forseti, "praeses", to be the older form of the name, first postulating an unattested Old High German equivalent *forasizo (cf. modern German Vorsitzender "one who presides"). but later preferring a derivation from fors, a "whirling stream" or "cataract", connected to the spring and the god's veneration by seagoing peoples. It is plausible that Fosite is the older name and Forseti a folk etymology. According to the German philologist Hans Kuhn the Germanic form Fosite is linguistically identical to Greek Poseidon, hence the original name must have been introduced before the Proto-Germanic sound change, probably via Greek sailors purchasing amber. The Greek traveller Pytheas of Massalia, who describes the amber trade, is known to have visited the region around 325 BC.
According to Snorri Sturluson in the Prose Edda, Forseti is the son of Baldr and Nanna. His home is Glitnir, its name, meaning "shining," refers to its silver ceiling and golden pillars, which radiated light that could be seen from a great distance. His is the best of courts; all those who come before him leave reconciled. This suggests skill in mediation and is in contrast to his fellow god Týr, who "is not called a reconciler of men." However, as de Vries points out, the only basis for associating Forseti with justice seems to have been his name; there is no corroborating evidence in Norse mythology. 'Puts to sleep all suits' or 'stills all strifes' may have been a late addition to the strophe Snorri cites, from which he derives the information.