What are some symbols the vikings put on their weapons?
In terms of just raw symbols without words, the Tiwaz rune was popular, as it represented Tyr. Tyr is to be twice named for victory in battle, and there is a sword with two Tiwaz runes on it. Thurisaz was another good rune, along with Mjolnir (thor’s hammer, which as a rune-like symbol was carved like an upside T. The fylfot (swastika) was another popular symbol.