What caused the credit crisis? Risky US consumers defaulting on their mortgages.
So what caused them to default on these loans? Well, the mortgages resetting to higher interest rates is one cause. But, the distribution of risky loans is uniform across American cities & neighborhoods. What was not uniformly distributed across neighborhoods was where the foreclosures began and where the steepest declines have taken place. The outer fringes of the exurbs were where the trouble started, then the suburbs - I wonder why? Far steeper declines have also been observed in the more sprawly US cities with little to no transit whereas areas close to central urban cores and cities with extensive transit have registered much lighter declines.
The oil price rise has been a gradual rise over the last several years, not a sudden 9-10 month thing. I'm not saying that the oil price is solely to blame for the current crisis but it's played a greater role than many people seem to believe. Risky mortgagors would have defaulted either way, but a major first trigger and the accelerant was the oil price.