There is a great irony behind the peace symbol. Its history is one of conflict and bloodshed. The modern use of this symbol was used by the Campaign for Nuclear Disarmament in 1958. It was commissioned by Bertrand Russell and designed by Gerald Holtom. According to Wikipedia ( or inaccuratedia ) It consisted of the semaphore sign for ‘N’ and ‘D’. Its popularity caught on in the 1960s with the hippie movement and has remained popular ever since.
The cross as we know it today is at least 2000 years old. It’s numerous names are the Teutonic cross, Nero’s cross and St Peters cross (the latter has been used to symbolise Satanism in recent years). The peace symbol is based on the broken arms of a crucifix. when a fire destroyed Rome in 64 AD, (the official account of this can be found in Tacitus’s The Annals of Imperial Rome). At the time there was speculation that Nero caused the fire, which lead Nero to blame the Christians as the scapegoat for the fire. Nero used the peace symbol on his coins, with a eagle. The result of this persecution lead to many Christians being tortured, I suspect mainly with crucifixion.
It is interesting to note that the Pythagorean’s used the reverse of this symbol as a sign of life. It has also been used as a Teutonic rune to mean death. The death rune can be seen to mirror that of the life rune. The life rune looking like that of a tree branching out. While the death rune is like the roots of a tree with no branches. This could be interpreted as the dualities between life and death, death the underworld where the roots of the tree of life (kabbalha) are kept.
Perhaps this is a combination of heaven (father sky) and the underworld (mother earth). And perhaps humanity is the bridge between these two worlds, as this is also often protrayed in symbolic forms of the kabbalah.
The teutonic runes of life and death make sense as a symbol of a tree when we take into account Yggdrasil, the world tree in Norse mythology. ‘This ash tree’s trunk reached up to the heavens, and its boughs spread out over all the countries of the Earth. Its roots reached down into the Underworld’ (http://www.treesforlife.org.uk/forest/mythfolk/ash.html).
In this light we are able to understand the symbolic significance of trees used to depict life and death in runes, but more importantly we can understand why the Peace symbol is one that has a history linked with death.