Over the last two decades public theology has emerged as a new and noteworthy theological movement in modern Christian scholarship. This article will retrace the historical contexts of this theological movement, including the traditions of the Puritan movement, the Scottish Enlightenment, political theology in Europe, and civil religion in North America. On the one hand, this paper will study the formative processes and historical profile of public theology; on the other it will argue that “involvement and participation in the public arena” has always been part of the intrinsic character of Christianity. In other words, while Christianity from its beginnings has always been a “public religion,” this character has only gradually revealed itself following the pre-modern period, under the strong influence of the Reformed tradition. From the middle of the twentieth!century onwards it has become an obvious and conscientious movement.