It is transliterated as ea, and the Anglo-Saxon rune poem glosses it as Jacob Grimm in his 1835 Teutonic Mythology (ch.
Grimm thus suggests that the Germans had adopted the name of Greek Ares as an epithet of their god of war, and Eresberc was literally an Areopagus.
Grimm further notes that in the Bavarian (Marcomannic) area, Tuesday (dies Martis) was known as Ertag, Iertag, Irtag, Eritag, Erchtag, Erichtag as opposed to the Swabian and Swiss (Alemannic) region where the same day is Ziestag as in Anglo-Saxon.
Grimm concludes that Ziu was known by the alternative name Eor, derived from Greek Ares, and also as Saxnot among the Saxons, identified as a god of the sword.
[1] In the farm life simulation game Stardew Valley, it represents a symbol of faith called Yoba.