I understand where your question is coming from; Forex is still a highly misunderstood asset class. We all here that it's the largest asset class in the world, yet very few people understand why, or how it really operates.
The simple answer is in fact "supply & demand"; what creates the supply and demand in currencies however, is what I believe you're asking.
Without getting into too much detail and technical jargon, there is need to exchange currency in order to facilitate business. For example if Toyota car manufacturer decides to open a car plant outside of Japan, say in the U.S., it must pay for all sorts of expenditures: contractors, raw materials, land to build a plant, etc. In order to do this, Toyota will "Buy" USD (Demand), and "Sell" JPY (Supply). When Toyota repatriates profits from the U.S. back to Japan, it will simply do the exact opposite of the above. Now imagine many thousands of businesses doing this. These are referred to by many names, including "Non-financial customers". These are businesses that need the underlying currency to conduct business.
Other major participants in the Forex world are "Equity managers". I am not talking about Forex managers here; rather, stock, bonds, and other equity classes. Take the example of a mutual fund manager in London who wants to invest in a company listed on the NYSE. To do this, the fund manager must first purchase USD, selling GBP, and then using the USD to buy the desired stock. This type of Forex transaction plays a much larger part in the Forex market than most think.
Banks of course do play a role, but most banks make money by charging fees, similar to Dukascopy, as opposed to trading on their accounts.
This is a highly simplified answer yet I believe it will point you in the right direction.
Supply and demand determines the price of ANYTHING, be it Forex-markets or groceries or whatever. Of course, it's possible to influence this process but there's no point in doing it without reason & doing so would be a financial suicide.
You can go around the markets in your country & start buying up every tomato you see, you are creating additional demand for tomatoes & since supply isn't going to rise instantly, the price of tomato will start going up, firstly, in the nearby regions where you are doing all the buying & depending on how much you are capable of buying & how quickly, prices could start rising in nearby countries & so on. But of course, it would be extremely risky or even stupid to do this unless you know for sure that for some reason, there's going to be a massive scarcity of tomatoes everywhere or there's going to be massive rise in its demand so that you are able to sell your stock of tomatoes at a decent profit (or at least without a significant loss).
Same happens on the Forex-markets, people buy currencies so that they could import stuff from other countries or traveling purposes or investment purposes, & exporters, banks & such have to sell the foreign currencies they receive from others, that's what drives prices in the Forex-markets, supply & demand for a given currency in relation to another.
More could be said on the issue but you should probably use Google if you wish to learn the in-depth details.
An omnipotent intelligence that moves the price of whatever instrument I have a position in the opposite direction. So you adopt a strategy of taking the opposite position of what you would normally take and guess what, it switches up on you and you get crushed once more. It's the most baffling phenomenon you will ever experience. The insanity of it all is I keep trading. Forex is fools gold. Nevertheless, I still believe I will defeat this beast one day. No longer do I believe I will get rich quick in forex. It's now all about something I read recently that spoke of a goal of 10 pips a day target. With money management and humility you may, maybe, stand a chance.
I think this question is one of the most stupid questions about forex. What's the difference who or what controls the price of tools . You never get a clear and coherent answer to this question and not any opinion can not be accepted , as an axiom. Even assuming knowledge of the correct answer, you will not be able to somehow affect the price movement or know her true direction . Therefore it is necessary to trade on the basis of market conditions. Better control of your mind and your actions to achieve its goals , rather than seek answers to such questions . Want to earn - start trading . Want to be in permanent loss - start thinking and looking for answers to such questions .
I don't think there is a person, organization, or oligarchy that controls Forex. Like the other respondents here, its supply and demand. The perception of value is actually more important than the reality. For-instance: investor's speculate not on the current relative monetary policy set by central banks. They instead invest based on the perception of how fundamental events might effect relative monetary policy in the future. I don't think that the market is controlled if for no other reason, that individual or organization would be the only buyer, and the other person the only seller. They would have all of the money and we would have no opportunity, let alone chance, to make some for ourselves. It would not be a market, so much as a proprietary system. If you want to find an instrument that will move big, look for divergence in relative monetary policy. Look to what fundamentals affect which currencies.