The Department of Political Science at Peradeniya is the first such department to be established in a university in Sri Lanka. However, even before its establishment as a fully fledged department in 1980, several courses in political science were offered in the Special Degree Programme in Economics. In 1969 the Chair of Political Science was created within the Department of Economics to facilitate further development of the subject. Prof. A. Jeyaratnam Wilson, an internationally recognized Sri Lankan political scientist, was appointed as the first Chair of Political Science. Soon separate General and Special Degree Programmes in Political Science became available, and students were admitted for postgraduate degrees in the subject. When the Department of Political Science was created eventually, those teachers who were conducting Political Science courses in the Department of Economics constituted the pioneer staff of the new department. Prof. S.U. Kodikara, who had succeeded Prof. Wilson as the Chair became the first Head of the new Department. Subsequently, Prof. W.A Wiswa Warnapala, a product of Peradeniya itself took over as the Chair in 1989. Another pioneer of the department was Dr. K.H Jayasinghe, who for a prolonged period of time handled the teaching in the subject almost single handedly.
After being established as a department, we can see a rapid growth in the subject in terms of courses taught, areas specialized in, and the number of students enrolled. In line with new developments in the subject, there was a gradual shift of emphasis towards studying more dynamic aspects of politics. Public administration, international relations, and comparative government were offered as special options. Towards the end of the 1990s further new courses on gender, conflict resolution, human rights, and political violence and terrorism were added to the departmental curriculum. With these developments there was a marked increase in the number of students offering the subject. Today this department has become the focal point in the study of Political Science in the country, providing guidance and resource persons in the preparation of syllabi, textbooks, and the conduct of a range of examinations. It is not surprising that most of the political science teachers of other Sri Lankan universities are drawn from among the products of Peradeniya. With a considerable number of postgraduate students and a senior staff with research experience, the department now lays great emphasis on research. It is also relevant to note that the department offers opportunities for visiting researchers. Over the years it has played host to foreign researchers, among whom are included several senior Indian and American scholars.