We present a theory of identity politics that builds on two ideas. First, when policy conflict renders a certain social divide—economic or cultural—salient, a voter identifies with her economic or cultural group. Second, the voter slants her beliefs towards the stereotype of the group she identifies with. We obtain three implications. First, voters’ beliefs are polarized along the distinctive features of salient groups. Second, if the salience of cultural policies increases, cultural conflict rises, redistributive conflict falls, and polarization becomes more correlated across issues. Third, economic shocks hurting conservative voters may trigger a switch to cultural identity, causing these voters to demand less redistribution. We discuss U.S. survey evidence in light of these implications.