An Unrepentant Liberal is a book of writings by an American professor of political science over a particular period of history. It includes an introduction by the author, who envisaged this book in his lifetime. Unfortunately, he died before its completion. There is, in addition, a preface by Ann Karson, his widow. This book contains a chapter from Dr Karson's major work, American Labor Unions and Politics, 1900–1918, and one from a previous writing on which it was based. Among other things, these and some of his scholarly articles and reviews about American labor tell of the discovery for which he is known, that the influence of Roman Catholicism should be added to previously noted factors accounting for the relative conservatism of American unions and the absence of a Labor Party in the United States. American labor in the early 20th Century was his research specialty. Other articles and reviews concern aspects of American government and politics, on which he regularly taught, and world affairs, as well as health issues and education. Topics include race relations, civil liberties, religion, socialism, the left, the right and foreign affairs.