According to Norse mythology, Einherjar are the best warriors, fallen heroes who have earned their place of honor in Valhalla. The holiday - Einheriar Day - was associated with the honoring of comrades-in-arms who fell in battle and the praise of weapons.
In its modern reincarnation, this day is associated with the veneration of Odin.
The legend testifies that only those warriors who fell in battle could get into Valhalla, who at the time of death did not let go of their weapons. Their souls are collected by the Valkyries and transferred to the halls of Odin or Freya, dividing among themselves all the dead warriors.
While in Valhalla, all Einherjar are constantly training and fighting each other. After all, according to legend, on the day of Ragnarok (the day of the last and decisive battle), 800 einheryas will come out of the 540 doors of Valhalla, which, led by Odin, will fight monsters and giants.