This is a study of royal government in the southern counties of the principality of Wales between the beginning of Edward I's conquest in 1277 and Henry VIII's 'act of Union'. This reprinted edition of the book, first published in 1972, includes a new introduction to incorporate recent writings on the subject. Part I discusses the administrative framework of Carmarthenshire and Cardiganshire and the way in which it evolved in response to the political needs and reactions of governors and governed. Part II is a comprehensive biographical calendar of the officers of English kings and princes in south Wales, based on a wide range of published and unpublished sources – their careers, experience and wealth. The book has been of great value to political and administrative historians, not only of Wales but of England too, and it also retains a value for students of Welsh society, and for literary and personal-name scholars. No comparable comprehensive study of the involvement of men (rarely of women) in public service in late-medieval Wales (or indeed England) exists for this level of society and government.