|Director of the University of Baltimore Center for International and Comparative Law|
|Alma mater||Harvard College (A.B.)
Oxford University (B.C.L.)
Oxford University (D.Phil.)
Harvard Law School (J.D.)
Mortimer Sellers (M.N.S. Sellers) (born 1959) is a law professor, philosopher, and historian. His work primarily concerns international law, comparative law, legal history, constitutional law, philosophy of law, and Roman law. He has been Regents Professor of the University System of Maryland since 2003, the highest honor in the UM System.  Sellers is best known for his books on republican constitutions, global justice, and universal human rights. He has been Director of the University of Baltimore Center for International and Comparative Law since 1994.
The interdisciplinary nature of Sellers' work has been consistent throughout his career. After graduating from Harvard College, summa cum laude, and Harvard Law School, Sellers studied history and philosophy at University College, Oxford as a Rhodes Scholar and Frank Knox Fellow, taking a degree in Civil Law in addition to his doctorate in Literae Humaniores. He has taught since 1989 at the University of Baltimore School of Law, and worked as a visitor at Georgetown University Law Center, Harvard University, Cambridge University, Bryn Mawr College, Erasmus University Rotterdam, and the Academy of International Law in The Hague.
Along with authors such as Philip Pettit and Jürgen Habermas, Sellers has been a leader in reviving republican ideas among lawyers and philosophers and in international politics. Sellers' conception of republicanism is more historically grounded than is usually the case, with greater emphasis on constitutional procedures and the concept of the common good. Sellers has written extensively on the republican antecedents of the French Revolution and the American Revolution, and the influence of legal history and legal education on political and social change. He has been an active participant in the development of post-communist and post-authoritarian legal institutions in Europe, Asia, and South America.
Sellers’ public influence arises in part from his editorship since 1996 of the American Society of International Law publication International Legal Theory and the comparative law journal Ius Gentium. Both publications were later converted into book series, published by Cambridge (International Legal Theory) and Springer (Ius Gentium). Much of the most important new thought in international and comparative law has been published in these two series, particularly by non-U.S. authors.
Sellers has been particularly active in promoting international cooperation between lawyers and judges to advance global justice, through the European-American Consortium for Legal Education (EACLE), the Brazil-United States Administration of Justice Project, and the Internationale Vereinigung für Rechts- und Sozialphilosophie (IVR). He frequently teaches, lectures, and publishes outside the United States. Sellers is married to the journalist Frances Stead Sellers.
Books Authored by M.N.S Sellers
- Republican Principles in International Law: The Fundamental Requirements of a Just World Order (Palgrave Macmillan, 2006)
- Republican Legal Theory: The History, Constitution and Purposes of Law in a Free State (Palgrave Macmillan, 2003)
- The Sacred Fire of Liberty: Republicanism, Liberalism and the Law (Macmillan, 1998)
- American Republicanism: Roman Ideology in the United States Constitution (Macmillan, 1994)
Books edited by M.N.S. Sellers
- Parochialism, Cosmopolitanism, and the Foundations of International Law (Cambridge, 2011)
- The Rule of Law in Comparative Perspective (with Tadeusz Tomaszewski) (Springer, 2010)
- The Internationalization of Law and Legal Education (with Jan Klabbers) (Springer, 2008)
- Autonomy in the Law (Springer, 2007)
- Universal Human Rights: Moral Order in a Divided World (with David Reidy) (Rowman and Littlefield, 2005)
- Place, Memory and Time (with Anthony F.C. Wallace and H. Dabbs Woodfin) (Newlin Foundation, 2004)
- The New World Order: Sovereignty, Human Rights, and the Self-Determination of Peoples (Berg, 1996)
- An Ethical Education: Community and Morality in the Multicultural University (Berg, 1994)