Traditions are important to people, or at least to many of us. They help to order our lives and to give them meaning. They tie us to the past and extend our concerns into the future. Yet the topic of tradition, and especially political tradition, has been largely ignored by contemporary political philosophers. In this article, the author discusses how the particular features of political traditions—features that distinguish them from other political traditions established in other places and times—contribute to their normativity. A political tradition is authoritative for people if it guides them in their political activity, giving them reasons that they would not otherwise have. By understanding these reasons, and their grounds, we can come to understand the moral significance of political traditions. Attention to the authority of political traditions, in turn, will illuminate how the political morality of societies depends on their past. That political morality is so dependent on the past is an important and neglected truth of political conservatism, one that the author hopes to bring into sharper focus.