In Norse mythology, Odin is the father or lord of the slain warriors in Valhalla.
Odin is the chief god most closely connected with Valhalla. The hall is described as belonging to him, and its chosen warriors, the einherjar, are often called his men or hosts. Valkyries select some battle-dead for this destination under his authority.
Odin’s connection with warriors is part of a wider and more complex character. He is also associated with wisdom, poetry, magic, prophecy, sovereignty, and the discovery of runes. His pursuit of knowledge includes sacrificing an eye at Mímir’s well and hanging himself on the world tree to gain the runes.
The phrase “father of the slain” is an epithet for Odin, but it should not be read as meaning that he literally fathered every warrior in Valhalla. It is a poetic title expressing his relationship with the battle-dead and his role as their divine leader.