Populism may seem like it has come out of nowhere, but it has been on the rise for a while. I argue that economic history and economic theory both provide ample grounds for anticipating that advanced stages of economic globalization would produce a political backlash. While the backlash may have been predictable, the specific form it took was less so. I distinguish between left-wing and right-wing variants of populism, which differ with respect to the societal cleavages that populist politicians highlight. The first has been predominant in Latin America, and the second in Europe. I argue that these different reactions are related to the relative salience of different types of globalization shocks.