Over the course of the 1850s and 1860s, during the first era of globalisation, the world experienced an unprecedented economic boom. Fuelling this expansion was an explosion in borrowing through the global bond market, which provided financing for the century's most costly and transformative innovation: the railroad. The boom predictably swelled into a series of bubbles that burst simultaneously in the early 1870s, cascading from one country to the next across the globe. Through the eyes of a cast that includes Karl Marx, Mark Twain and the Rothschild family, Liaquat Ahamed weaves a compelling narrative of build-up, collapse and world-changing aftermath.