As we try to sort out the causes and consequences of armed conflicts around the globe, we seldom ask the question: where do all those weapons come from that make these wars possible? With the United States racking up a record shattering $66.3 billion in overseas weapons sales last year, the question has become even more pressing. This month, historian Jonathan A. Grant looks at the history of the governments and individuals who have created a global trade in armaments. Except when they run afoul of the law, as Russian arms dealer Victor Bout did in 2011, these men tend to operate out of public view but the impact they have had on societies around the world is hard to over-estimate.