Winston Churchill used a V sign in both versions to symbolise 'V for Victory' during World War II. US President Richard Nixon also used the victory sign.
The insulting version originates, allegedly, from around the time of the Hundred Years War, when captured English archers would have their two bow fingers cut off to prevent them using their favoured weapon. The archers began to use the V gesture, palm inwards, to show the enemy that they could still attack them. In the modern world, the gesture has a very confused meaning, as it depends on which culture the people using belong to, and what they are trying to signify.
The Peace gesture was (and is) commonly used by anti-war protesters.