Only some wars in the past have been started because of or also affecting religion. Many wars like world war two and the war on terror affected religion but were not one of the main causes, unlike the catholic crusades wars like the Vietnam war had nothing or next to nothing to do with religion as far as I know and was mostly for America to stop the spread of communism. Even if many wars have been started because of religion, that does not mean that there aren't other reasons that wars were started such as imperial expansion.
Have you said "ideologies" instead of "religion", I would have chosen Yes. But, generally, I don't think that religion is the cause of the majority of wars in the world. Sure, it has caused some, and it has that "They're infidels, they will burn in hell" tribal mentality, which may contribute to aggravation. Ultimately, I think that wars are caused by human greed - wanting more land, wanting to control more people and resources etc.
For instance, you couldn't attribute the causes of WWI or WWII to religion, but you could attribute them to ideologies and greed.