The breakdown of the economic and political arrangement described in Chapter One contributed to increasing social and political polarization in the 1960s, leading both to the strengthening of labor and leftist mobilization and to the crisis of traditional parties and government. Violence and repression became an integral part of politics to an extent previously unimaginable in a society accustomed to muffled controversies and consensual conflict resolution. Military government was also largely unknown in the country until the 1973 coup d'etat. As Uruguay entered a period of radicalized unrest, all the actors involved had to rethink their stances on the causes and consequences of political disorder and violence. These national developments shaped the formulation of a new leftist project, giving fresh meaning to the idea that revolutionary transformation was a logical product of historical forces and a desired goal for the country. International events had also a profound influence on the Uruguayan left, starting with the impact of the Cuban revolution on political discourse and behavior. This chapter describes how leftist parties and groups reacted to all these challenges in order to provide the historical and conceptual background for further analysis of their later relations to the transnational human rights movement.