The sharp spikes and dips in oil prices since February are in large part due to geopolitical issues that result in direct intervention in oil prices. Despite this intervention, however, supply and demand are the ultimate determining factor as witnessed over the past months.
Current Oil Prices
Predicted Oil Prices from the US Energy Information Administration (dotted line)
As you can see we are close to prices that were predicted back in Jan 2018 based on supply and demand.
Moral of the story:
Prices are determined by supply and demand (i.e. fundamentals) over the long term.