Surveying three generations of comparative sociologists, separated by abrupt discontinuities, the study reaches the conclusion that the original promise of comparative sociology set in motion a century ago remains largely unfulfilled. It will then be argued that the work of the third generation of comparative sociologists on civilizational analysis and multiple modernities can redeem the promise of comparative sociology by rectifying the neglect of developmental patterns in other civilizations and recovering the fundamental relevance of the periphery. The third generation is thus seeking to undo the erasure of the historical experience of a very sizeable portion of humankind from the foundation of social theory. This argument is illustrated by selective reference to the concept of the nation-state, and comparisons of civilizational processes and developmental patterns that stem from different religions and traditions and generate varieties of nationalism, alternative modernities and patterns of secularization.