The worldwide financial crisis that began in 2007 was set off by the collapse of the subprime mortgage market in the USA. The crisis simultaneously reverberated to banks around the world, and eventually brought about a worldwide recession. The biggest banks in the developed world got in trouble because they were pursuing the same strategies to make profit as the American banks. They had joined the market in the USA for mortgage-backed securities and funded them by borrowing in the asset-backed commercial paper market. When the housing market turned down, they suffered the same fate as their US counterparts. Financial deregulation played a complex role in this process. Most of the banks that participated in this market came from countries where financial deregulation occurred. But not all banks from countries with financial deregulation entered this market. Countries with high levels of financial deregulation also experienced deeper recessions, suggesting that in the home market, banks had taken on riskier loans as well. Our study makes a broader theoretical point, suggesting that subsequent studies of global finance and financial markets need to consider the identities and strategies of the banks as their tactics explain a lot about how the global markets for different financial products are structured.