The Yom Kippur war of 1973 caused the credit crunch and collapse of the world financial system in 2008.
Let me explain. The Yom Kippur War was initiated on 6th October 1973, the holiest day in the Jewish calendar, when Syria and Egypt jointly attacked Israel. It was only the support of the United States, which sent $2 billion of arms, that enabled Israel to repell its assailants. However, the support that the United States provided to Israel triggered OPEC, the Arab oil-production cartel, into raising oil prices and cutting oil production, and this caused the worldwide oil crisis of 1973-1974.
Prior to the crisis, the average rate of economic growth in the West had been around 5 percent; after the crisis, growth reduced to zero, and inflation rose to around 10 percent. The late 1970s, then, was an era of stagflation, and its consequence was to destroy the Keynesian economic consensus, with its belief in the importance of government taxation and expenditure. In its place, as Thatcher and Reagan came to power in 1979 and 1980, were the economics of Milton Friedman, with its emphasis on low taxation and the unregulated free market. This belief in the unregulated free market permitted the growth of financial derivatives capable of hiding debt, and this ultimately led to the collapse of the world financial system in 2008.
And the role of sub-prime mortgages in the USA? Well, the problem with the growth of financial derivatives is that they created an unstable system, and as Professor Peter Cox pointed out in High Anxieties: The Mathematics of Chaos, when an unstable system collapses, the particular eddy which causes it to collapse is not really relevant, it is the instability itself which is the culprit.